/*
 * ffmpeg option parsing
 * copyright (c) 2018 Taner Sener ( tanersener gmail com )
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * This file is the modified version of ffmpeg_opt.c file living in ffmpeg source code under the fftools folder. We
 * manually update it each time we depend on a new ffmpeg version. Below you can see the list of changes applied
 * by us to develop mobile-ffmpeg and later ffmpeg-kit libraries.
 *
 * mobile-ffmpeg / ffmpeg-kit changes by Taner Sener
 *
 * 08.2020
 * --------------------------------------------------------
 * - read_file renamed as fftools_read_file
 *
 * 01.2020
 * --------------------------------------------------------
 * - ffprobe support (added ffmpeg_ prefix to options used by ffmpeg, logs with AV_LOG_INFO level migrated to
 *   use AV_LOG_STDERR)
 *
 * 12.2019
 * --------------------------------------------------------
 * - concurrent execution support ("__thread" specifier added to variables used by multiple threads, static keyword
 *   removed from methods called by both ffmpeg and ffprobe, options replaced with global_options, options definition
 *   deleted)
 *
 * 08.2018
 * --------------------------------------------------------
 * - fftools_ prefix added to file name and parent headers
 *
 * 07.2018
 * --------------------------------------------------------
 * - parentheses placed around assignments in condition to prevent -Wparentheses warning
 */

#include "config.h"

#include <stdint.h>

#if HAVE_SYS_RESOURCE_H
#include <sys/time.h>
#include <sys/resource.h>
#endif

#include "fftools_ffmpeg.h"
#include "fftools_fopen_utf8.h"
#include "fftools_cmdutils.h"

#include "libavformat/avformat.h"

#include "libavcodec/avcodec.h"
#include "libavcodec/bsf.h"

#include "libavfilter/avfilter.h"

#include "libavutil/avassert.h"
#include "libavutil/avstring.h"
#include "libavutil/avutil.h"
#include "libavutil/bprint.h"
#include "libavutil/channel_layout.h"
#include "libavutil/getenv_utf8.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/fifo.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/pixfmt.h"

#define DEFAULT_PASS_LOGFILENAME_PREFIX "ffmpeg2pass"

#define SPECIFIER_OPT_FMT_str  "%s"
#define SPECIFIER_OPT_FMT_i    "%i"
#define SPECIFIER_OPT_FMT_i64  "%"PRId64
#define SPECIFIER_OPT_FMT_ui64 "%"PRIu64
#define SPECIFIER_OPT_FMT_f    "%f"
#define SPECIFIER_OPT_FMT_dbl  "%lf"

static const char *const opt_name_codec_names[]               = {"c", "codec", "acodec", "vcodec", "scodec", "dcodec", NULL};
static const char *const opt_name_audio_channels[]            = {"ac", NULL};
static const char *const opt_name_audio_ch_layouts[]          = {"channel_layout", "ch_layout", NULL};
static const char *const opt_name_audio_sample_rate[]         = {"ar", NULL};
static const char *const opt_name_frame_rates[]               = {"r", NULL};
static const char *const opt_name_max_frame_rates[]           = {"fpsmax", NULL};
static const char *const opt_name_frame_sizes[]               = {"s", NULL};
static const char *const opt_name_frame_pix_fmts[]            = {"pix_fmt", NULL};
static const char *const opt_name_ts_scale[]                  = {"itsscale", NULL};
static const char *const opt_name_hwaccels[]                  = {"hwaccel", NULL};
static const char *const opt_name_hwaccel_devices[]           = {"hwaccel_device", NULL};
static const char *const opt_name_hwaccel_output_formats[]    = {"hwaccel_output_format", NULL};
static const char *const opt_name_autorotate[]                = {"autorotate", NULL};
static const char *const opt_name_autoscale[]                 = {"autoscale", NULL};
static const char *const opt_name_max_frames[]                = {"frames", "aframes", "vframes", "dframes", NULL};
static const char *const opt_name_bitstream_filters[]         = {"bsf", "absf", "vbsf", NULL};
static const char *const opt_name_codec_tags[]                = {"tag", "atag", "vtag", "stag", NULL};
static const char *const opt_name_sample_fmts[]               = {"sample_fmt", NULL};
static const char *const opt_name_qscale[]                    = {"q", "qscale", NULL};
static const char *const opt_name_forced_key_frames[]         = {"forced_key_frames", NULL};
static const char *const opt_name_fps_mode[]                  = {"fps_mode", NULL};
static const char *const opt_name_force_fps[]                 = {"force_fps", NULL};
static const char *const opt_name_frame_aspect_ratios[]       = {"aspect", NULL};
static const char *const opt_name_rc_overrides[]              = {"rc_override", NULL};
static const char *const opt_name_intra_matrices[]            = {"intra_matrix", NULL};
static const char *const opt_name_inter_matrices[]            = {"inter_matrix", NULL};
static const char *const opt_name_chroma_intra_matrices[]     = {"chroma_intra_matrix", NULL};
static const char *const opt_name_top_field_first[]           = {"top", NULL};
static const char *const opt_name_presets[]                   = {"pre", "apre", "vpre", "spre", NULL};
static const char *const opt_name_copy_initial_nonkeyframes[] = {"copyinkf", NULL};
static const char *const opt_name_copy_prior_start[]          = {"copypriorss", NULL};
static const char *const opt_name_filters[]                   = {"filter", "af", "vf", NULL};
static const char *const opt_name_filter_scripts[]            = {"filter_script", NULL};
static const char *const opt_name_reinit_filters[]            = {"reinit_filter", NULL};
static const char *const opt_name_fix_sub_duration[]          = {"fix_sub_duration", NULL};
static const char *const opt_name_canvas_sizes[]              = {"canvas_size", NULL};
static const char *const opt_name_pass[]                      = {"pass", NULL};
static const char *const opt_name_passlogfiles[]              = {"passlogfile", NULL};
static const char *const opt_name_max_muxing_queue_size[]     = {"max_muxing_queue_size", NULL};
static const char *const opt_name_muxing_queue_data_threshold[] = {"muxing_queue_data_threshold", NULL};
static const char *const opt_name_guess_layout_max[]          = {"guess_layout_max", NULL};
static const char *const opt_name_apad[]                      = {"apad", NULL};
static const char *const opt_name_discard[]                   = {"discard", NULL};
static const char *const opt_name_disposition[]               = {"disposition", NULL};
static const char *const opt_name_time_bases[]                = {"time_base", NULL};
static const char *const opt_name_enc_time_bases[]            = {"enc_time_base", NULL};
static const char *const opt_name_bits_per_raw_sample[]       = {"bits_per_raw_sample", NULL};

#define WARN_MULTIPLE_OPT_USAGE(name, type, so, st)\
{\
    char namestr[128] = "";\
    const char *spec = so->specifier && so->specifier[0] ? so->specifier : "";\
    for (i = 0; opt_name_##name[i]; i++)\
        av_strlcatf(namestr, sizeof(namestr), "-%s%s", opt_name_##name[i], opt_name_##name[i+1] ? (opt_name_##name[i+2] ? ", " : " or ") : "");\
    av_log(NULL, AV_LOG_WARNING, "Multiple %s options specified for stream %d, only the last option '-%s%s%s "SPECIFIER_OPT_FMT_##type"' will be used.\n",\
           namestr, st->index, opt_name_##name[0], spec[0] ? ":" : "", spec, so->u.type);\
}

#define MATCH_PER_STREAM_OPT(name, type, outvar, fmtctx, st)\
{\
    int i, ret, matches = 0;\
    SpecifierOpt *so;\
    for (i = 0; i < o->nb_ ## name; i++) {\
        char *spec = o->name[i].specifier;\
        if ((ret = check_stream_specifier(fmtctx, st, spec)) > 0) {\
            outvar = o->name[i].u.type;\
            so = &o->name[i];\
            matches++;\
        } else if (ret < 0)\
            exit_program(1);\
    }\
    if (matches > 1)\
       WARN_MULTIPLE_OPT_USAGE(name, type, so, st);\
}

#define MATCH_PER_TYPE_OPT(name, type, outvar, fmtctx, mediatype)\
{\
    int i;\
    for (i = 0; i < o->nb_ ## name; i++) {\
        char *spec = o->name[i].specifier;\
        if (!strcmp(spec, mediatype))\
            outvar = o->name[i].u.type;\
    }\
}

__thread HWDevice *filter_hw_device;

__thread char *vstats_filename;
__thread char *sdp_filename;

__thread float audio_drift_threshold = 0.1;
__thread float dts_delta_threshold   = 10;
__thread float dts_error_threshold   = 3600*30;

__thread int audio_volume      = 256;
__thread int audio_sync_method = 0;
__thread enum VideoSyncMethod video_sync_method = VSYNC_AUTO;
__thread float frame_drop_threshold = 0;
__thread int do_benchmark      = 0;
__thread int do_benchmark_all  = 0;
__thread int do_hex_dump       = 0;
__thread int do_pkt_dump       = 0;
__thread int copy_ts           = 0;
__thread int start_at_zero     = 0;
__thread int copy_tb           = -1;
__thread int debug_ts          = 0;
__thread int exit_on_error     = 0;
__thread int abort_on_flags    = 0;
__thread int print_stats       = -1;
__thread int qp_hist           = 0;
__thread int stdin_interaction = 1;
__thread float max_error_rate  = 2.0/3;
__thread char *filter_nbthreads = NULL;
__thread int filter_complex_nbthreads = 0;
__thread int vstats_version = 2;
__thread int auto_conversion_filters = 1;
__thread int64_t stats_period = 500000;


__thread int file_overwrite     = 0;
__thread int no_file_overwrite  = 0;
__thread int do_psnr            = 0;
__thread int input_stream_potentially_available = 0;
__thread int ignore_unknown_streams = 0;
__thread int copy_unknown_streams = 0;
__thread int recast_media = 0;
__thread int find_stream_info = 1;

extern __thread OptionDef *ffmpeg_options;

void uninit_options(OptionsContext *o)
{
    const OptionDef *po = ffmpeg_options;
    int i;

    /* all OPT_SPEC and OPT_STRING can be freed in generic way */
    while (po->name) {
        void *dst = (uint8_t*)o + po->u.off;

        if (po->flags & OPT_SPEC) {
            SpecifierOpt **so = dst;
            int i, *count = (int*)(so + 1);
            for (i = 0; i < *count; i++) {
                av_freep(&(*so)[i].specifier);
                if (po->flags & OPT_STRING)
                    av_freep(&(*so)[i].u.str);
            }
            av_freep(so);
            *count = 0;
        } else if (po->flags & OPT_OFFSET && po->flags & OPT_STRING)
            av_freep(dst);
        po++;
    }

    for (i = 0; i < o->nb_stream_maps; i++)
        av_freep(&o->stream_maps[i].linklabel);
    av_freep(&o->stream_maps);
    av_freep(&o->audio_channel_maps);
    av_freep(&o->streamid_map);
    av_freep(&o->attachments);
}

void init_options(OptionsContext *o)
{
    memset(o, 0, sizeof(*o));

    o->stop_time = INT64_MAX;
    o->mux_max_delay  = 0.7;
    o->start_time     = AV_NOPTS_VALUE;
    o->start_time_eof = AV_NOPTS_VALUE;
    o->recording_time = INT64_MAX;
    o->limit_filesize = UINT64_MAX;
    o->chapters_input_file = INT_MAX;
    o->accurate_seek  = 1;
    o->thread_queue_size = -1;
    o->input_sync_ref = -1;
}

int show_hwaccels(void *optctx, const char *opt, const char *arg)
{
    enum AVHWDeviceType type = AV_HWDEVICE_TYPE_NONE;

    av_log(NULL, AV_LOG_STDERR, "Hardware acceleration methods:\n");
    while ((type = av_hwdevice_iterate_types(type)) !=
           AV_HWDEVICE_TYPE_NONE)
        av_log(NULL, AV_LOG_STDERR, "%s\n", av_hwdevice_get_type_name(type));
    av_log(NULL, AV_LOG_STDERR, "\n");
    return 0;
}

/* return a copy of the input with the stream specifiers removed from the keys */
AVDictionary *strip_specifiers(AVDictionary *dict)
{
    const AVDictionaryEntry *e = NULL;
    AVDictionary    *ret = NULL;

    while ((e = av_dict_get(dict, "", e, AV_DICT_IGNORE_SUFFIX))) {
        char *p = strchr(e->key, ':');

        if (p)
            *p = 0;
        av_dict_set(&ret, e->key, e->value, 0);
        if (p)
            *p = ':';
    }
    return ret;
}

int parse_and_set_vsync(const char *arg, int *vsync_var, int file_idx, int st_idx, int is_global)
{
    if      (!av_strcasecmp(arg, "cfr"))         *vsync_var = VSYNC_CFR;
    else if (!av_strcasecmp(arg, "vfr"))         *vsync_var = VSYNC_VFR;
    else if (!av_strcasecmp(arg, "passthrough")) *vsync_var = VSYNC_PASSTHROUGH;
    else if (!av_strcasecmp(arg, "drop"))        *vsync_var = VSYNC_DROP;
    else if (!is_global && !av_strcasecmp(arg, "auto"))  *vsync_var = VSYNC_AUTO;
    else if (!is_global) {
        av_log(NULL, AV_LOG_FATAL, "Invalid value %s specified for fps_mode of #%d:%d.\n", arg, file_idx, st_idx);
        exit_program(1);
    }

    if (is_global && *vsync_var == VSYNC_AUTO) {
        video_sync_method = parse_number_or_die("vsync", arg, OPT_INT, VSYNC_AUTO, VSYNC_VFR);
        av_log(NULL, AV_LOG_WARNING, "Passing a number to -vsync is deprecated,"
               " use a string argument as described in the manual.\n");
    }
    return 0;
}

int apply_sync_offsets(void)
{
    for (int i = 0; i < nb_input_files; i++) {
        InputFile *ref, *self = input_files[i];
        int64_t adjustment;
        int64_t self_start_time, ref_start_time, self_seek_start, ref_seek_start;
        int start_times_set = 1;

        if (self->input_sync_ref == -1 || self->input_sync_ref == i) continue;
        if (self->input_sync_ref >= nb_input_files || self->input_sync_ref < -1) {
            av_log(NULL, AV_LOG_FATAL, "-isync for input %d references non-existent input %d.\n", i, self->input_sync_ref);
            exit_program(1);
        }

        if (copy_ts && !start_at_zero) {
            av_log(NULL, AV_LOG_FATAL, "Use of -isync requires that start_at_zero be set if copyts is set.\n");
            exit_program(1);
        }

        ref = input_files[self->input_sync_ref];
        if (ref->input_sync_ref != -1 && ref->input_sync_ref != self->input_sync_ref) {
            av_log(NULL, AV_LOG_ERROR, "-isync for input %d references a resynced input %d. Sync not set.\n", i, self->input_sync_ref);
            continue;
        }

        if (self->ctx->start_time_realtime != AV_NOPTS_VALUE && ref->ctx->start_time_realtime != AV_NOPTS_VALUE) {
            self_start_time = self->ctx->start_time_realtime;
            ref_start_time  =  ref->ctx->start_time_realtime;
        } else if (self->ctx->start_time != AV_NOPTS_VALUE && ref->ctx->start_time != AV_NOPTS_VALUE) {
            self_start_time = self->ctx->start_time;
            ref_start_time  =  ref->ctx->start_time;
        } else {
            start_times_set = 0;
        }

        if (start_times_set) {
            self_seek_start = self->start_time == AV_NOPTS_VALUE ? 0 : self->start_time;
            ref_seek_start  =  ref->start_time == AV_NOPTS_VALUE ? 0 :  ref->start_time;

            adjustment = (self_start_time - ref_start_time) + !copy_ts*(self_seek_start - ref_seek_start) + ref->input_ts_offset;

            self->ts_offset += adjustment;

            av_log(NULL, AV_LOG_INFO, "Adjusted ts offset for Input #%d by %"PRId64" us to sync with Input #%d.\n", i, adjustment, self->input_sync_ref);
        } else {
            av_log(NULL, AV_LOG_INFO, "Unable to identify start times for Inputs #%d and %d both. No sync adjustment made.\n", i, self->input_sync_ref);
        }
    }

    return 0;
}

int opt_filter_threads(void *optctx, const char *opt, const char *arg)
{
    av_free(filter_nbthreads);
    filter_nbthreads = av_strdup(arg);
    return 0;
}

int opt_abort_on(void *optctx, const char *opt, const char *arg)
{
    static const AVOption opts[] = {
        { "abort_on"           , NULL, 0, AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT64_MIN, (double)INT64_MAX,   .unit = "flags" },
        { "empty_output"       , NULL, 0, AV_OPT_TYPE_CONST, { .i64 = ABORT_ON_FLAG_EMPTY_OUTPUT        }, .unit = "flags" },
        { "empty_output_stream", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = ABORT_ON_FLAG_EMPTY_OUTPUT_STREAM }, .unit = "flags" },
        { NULL },
    };
    static const AVClass class = {
        .class_name = "",
        .item_name  = av_default_item_name,
        .option     = opts,
        .version    = LIBAVUTIL_VERSION_INT,
    };
    const AVClass *pclass = &class;

    return av_opt_eval_flags(&pclass, &opts[0], arg, &abort_on_flags);
}

int opt_stats_period(void *optctx, const char *opt, const char *arg)
{
    int64_t user_stats_period = parse_time_or_die(opt, arg, 1);

    if (user_stats_period <= 0) {
        av_log(NULL, AV_LOG_ERROR, "stats_period %s must be positive.\n", arg);
        return AVERROR(EINVAL);
    }

    stats_period = user_stats_period;
    av_log(NULL, AV_LOG_INFO, "ffmpeg stats and -progress period set to %s.\n", arg);

    return 0;
}

int opt_audio_codec(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "codec:a", arg, ffmpeg_options);
}

int opt_video_codec(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "codec:v", arg, ffmpeg_options);
}

int opt_subtitle_codec(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "codec:s", arg, ffmpeg_options);
}

int opt_data_codec(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "codec:d", arg, ffmpeg_options);
}

int opt_map(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    StreamMap *m = NULL;
    int i, negative = 0, file_idx, disabled = 0;
    int sync_file_idx = -1, sync_stream_idx = 0;
    char *p, *sync;
    char *map;
    char *allow_unused;

    if (*arg == '-') {
        negative = 1;
        arg++;
    }
    map = av_strdup(arg);
    if (!map)
        return AVERROR(ENOMEM);

    /* parse sync stream first, just pick first matching stream */
    if ((sync = strchr(map, ','))) {
        *sync = 0;
        sync_file_idx = strtol(sync + 1, &sync, 0);
        if (sync_file_idx >= nb_input_files || sync_file_idx < 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid sync file index: %d.\n", sync_file_idx);
            exit_program(1);
        }
        if (*sync)
            sync++;
        for (i = 0; i < input_files[sync_file_idx]->nb_streams; i++)
            if (check_stream_specifier(input_files[sync_file_idx]->ctx,
                                       input_files[sync_file_idx]->ctx->streams[i], sync) == 1) {
                sync_stream_idx = i;
                break;
            }
        if (i == input_files[sync_file_idx]->nb_streams) {
            av_log(NULL, AV_LOG_FATAL, "Sync stream specification in map %s does not "
                                       "match any streams.\n", arg);
            exit_program(1);
        }
        if (input_streams[input_files[sync_file_idx]->ist_index + sync_stream_idx]->user_set_discard == AVDISCARD_ALL) {
            av_log(NULL, AV_LOG_FATAL, "Sync stream specification in map %s matches a disabled input "
                                       "stream.\n", arg);
            exit_program(1);
        }
    }


    if (map[0] == '[') {
        /* this mapping refers to lavfi output */
        const char *c = map + 1;
        GROW_ARRAY(o->stream_maps, o->nb_stream_maps);
        m = &o->stream_maps[o->nb_stream_maps - 1];
        m->linklabel = av_get_token(&c, "]");
        if (!m->linklabel) {
            av_log(NULL, AV_LOG_ERROR, "Invalid output link label: %s.\n", map);
            exit_program(1);
        }
    } else {
        if ((allow_unused = strchr(map, '?')))
            *allow_unused = 0;
        file_idx = strtol(map, &p, 0);
        if (file_idx >= nb_input_files || file_idx < 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid input file index: %d.\n", file_idx);
            exit_program(1);
        }
        if (negative)
            /* disable some already defined maps */
            for (i = 0; i < o->nb_stream_maps; i++) {
                m = &o->stream_maps[i];
                if (file_idx == m->file_index &&
                    check_stream_specifier(input_files[m->file_index]->ctx,
                                           input_files[m->file_index]->ctx->streams[m->stream_index],
                                           *p == ':' ? p + 1 : p) > 0)
                    m->disabled = 1;
            }
        else
            for (i = 0; i < input_files[file_idx]->nb_streams; i++) {
                if (check_stream_specifier(input_files[file_idx]->ctx, input_files[file_idx]->ctx->streams[i],
                            *p == ':' ? p + 1 : p) <= 0)
                    continue;
                if (input_streams[input_files[file_idx]->ist_index + i]->user_set_discard == AVDISCARD_ALL) {
                    disabled = 1;
                    continue;
                }
                GROW_ARRAY(o->stream_maps, o->nb_stream_maps);
                m = &o->stream_maps[o->nb_stream_maps - 1];

                m->file_index   = file_idx;
                m->stream_index = i;

                if (sync_file_idx >= 0) {
                    m->sync_file_index   = sync_file_idx;
                    m->sync_stream_index = sync_stream_idx;
                } else {
                    m->sync_file_index   = file_idx;
                    m->sync_stream_index = i;
                }
            }
    }

    if (!m) {
        if (allow_unused) {
            av_log(NULL, AV_LOG_VERBOSE, "Stream map '%s' matches no streams; ignoring.\n", arg);
        } else if (disabled) {
            av_log(NULL, AV_LOG_FATAL, "Stream map '%s' matches disabled streams.\n"
                                       "To ignore this, add a trailing '?' to the map.\n", arg);
            exit_program(1);
        } else {
            av_log(NULL, AV_LOG_FATAL, "Stream map '%s' matches no streams.\n"
                                       "To ignore this, add a trailing '?' to the map.\n", arg);
            exit_program(1);
        }
    }

    av_freep(&map);
    return 0;
}

int opt_attach(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    GROW_ARRAY(o->attachments, o->nb_attachments);
    o->attachments[o->nb_attachments - 1] = arg;
    return 0;
}

int opt_map_channel(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    int n;
    AVStream *st;
    AudioChannelMap *m;
    char *allow_unused;
    char *mapchan;
    mapchan = av_strdup(arg);
    if (!mapchan)
        return AVERROR(ENOMEM);

    GROW_ARRAY(o->audio_channel_maps, o->nb_audio_channel_maps);
    m = &o->audio_channel_maps[o->nb_audio_channel_maps - 1];

    /* muted channel syntax */
    n = sscanf(arg, "%d:%d.%d", &m->channel_idx, &m->ofile_idx, &m->ostream_idx);
    if ((n == 1 || n == 3) && m->channel_idx == -1) {
        m->file_idx = m->stream_idx = -1;
        if (n == 1)
            m->ofile_idx = m->ostream_idx = -1;
        av_free(mapchan);
        return 0;
    }

    /* normal syntax */
    n = sscanf(arg, "%d.%d.%d:%d.%d",
               &m->file_idx,  &m->stream_idx, &m->channel_idx,
               &m->ofile_idx, &m->ostream_idx);

    if (n != 3 && n != 5) {
        av_log(NULL, AV_LOG_FATAL, "Syntax error, mapchan usage: "
               "[file.stream.channel|-1][:syncfile:syncstream]\n");
        exit_program(1);
    }

    if (n != 5) // only file.stream.channel specified
        m->ofile_idx = m->ostream_idx = -1;

    /* check input */
    if (m->file_idx < 0 || m->file_idx >= nb_input_files) {
        av_log(NULL, AV_LOG_FATAL, "mapchan: invalid input file index: %d\n",
               m->file_idx);
        exit_program(1);
    }
    if (m->stream_idx < 0 ||
        m->stream_idx >= input_files[m->file_idx]->nb_streams) {
        av_log(NULL, AV_LOG_FATAL, "mapchan: invalid input file stream index #%d.%d\n",
               m->file_idx, m->stream_idx);
        exit_program(1);
    }
    st = input_files[m->file_idx]->ctx->streams[m->stream_idx];
    if (st->codecpar->codec_type != AVMEDIA_TYPE_AUDIO) {
        av_log(NULL, AV_LOG_FATAL, "mapchan: stream #%d.%d is not an audio stream.\n",
               m->file_idx, m->stream_idx);
        exit_program(1);
    }
    /* allow trailing ? to map_channel */
    if ((allow_unused = strchr(mapchan, '?')))
        *allow_unused = 0;
    if (m->channel_idx < 0 || m->channel_idx >= st->codecpar->ch_layout.nb_channels ||
        input_streams[input_files[m->file_idx]->ist_index + m->stream_idx]->user_set_discard == AVDISCARD_ALL) {
        if (allow_unused) {
            av_log(NULL, AV_LOG_VERBOSE, "mapchan: invalid audio channel #%d.%d.%d\n",
                    m->file_idx, m->stream_idx, m->channel_idx);
        } else {
            av_log(NULL, AV_LOG_FATAL,  "mapchan: invalid audio channel #%d.%d.%d\n"
                    "To ignore this, add a trailing '?' to the map_channel.\n",
                    m->file_idx, m->stream_idx, m->channel_idx);
            exit_program(1);
        }

    }
    av_free(mapchan);
    return 0;
}

int opt_sdp_file(void *optctx, const char *opt, const char *arg)
{
    av_free(sdp_filename);
    sdp_filename = av_strdup(arg);
    return 0;
}

#if CONFIG_VAAPI
int opt_vaapi_device(void *optctx, const char *opt, const char *arg)
{
    const char *prefix = "vaapi:";
    char *tmp;
    int err;
    tmp = av_asprintf("%s%s", prefix, arg);
    if (!tmp)
        return AVERROR(ENOMEM);
    err = hw_device_init_from_string(tmp, NULL);
    av_free(tmp);
    return err;
}
#endif

#if CONFIG_QSV
int opt_qsv_device(void *optctx, const char *opt, const char *arg)
{
    const char *prefix = "qsv=__qsv_device:hw_any,child_device=";
    int err;
    char *tmp = av_asprintf("%s%s", prefix, arg);

    if (!tmp)
        return AVERROR(ENOMEM);

    err = hw_device_init_from_string(tmp, NULL);
    av_free(tmp);

    return err;
}
#endif

int opt_init_hw_device(void *optctx, const char *opt, const char *arg)
{
    if (!strcmp(arg, "list")) {
        enum AVHWDeviceType type = AV_HWDEVICE_TYPE_NONE;
        av_log(NULL, AV_LOG_STDERR, "Supported hardware device types:\n");
        while ((type = av_hwdevice_iterate_types(type)) !=
               AV_HWDEVICE_TYPE_NONE)
            av_log(NULL, AV_LOG_STDERR, "%s\n", av_hwdevice_get_type_name(type));
        av_log(NULL, AV_LOG_STDERR, "\n");
        exit_program(0);
    } else {
        return hw_device_init_from_string(arg, NULL);
    }
}

int opt_filter_hw_device(void *optctx, const char *opt, const char *arg)
{
    if (filter_hw_device) {
        av_log(NULL, AV_LOG_ERROR, "Only one filter device can be used.\n");
        return AVERROR(EINVAL);
    }
    filter_hw_device = hw_device_get_by_name(arg);
    if (!filter_hw_device) {
        av_log(NULL, AV_LOG_ERROR, "Invalid filter device %s.\n", arg);
        return AVERROR(EINVAL);
    }
    return 0;
}

/**
 * Parse a metadata specifier passed as 'arg' parameter.
 * @param arg  metadata string to parse
 * @param type metadata type is written here -- g(lobal)/s(tream)/c(hapter)/p(rogram)
 * @param index for type c/p, chapter/program index is written here
 * @param stream_spec for type s, the stream specifier is written here
 */
void parse_meta_type(char *arg, char *type, int *index, const char **stream_spec)
{
    if (*arg) {
        *type = *arg;
        switch (*arg) {
        case 'g':
            break;
        case 's':
            if (*(++arg) && *arg != ':') {
                av_log(NULL, AV_LOG_FATAL, "Invalid metadata specifier %s.\n", arg);
                exit_program(1);
            }
            *stream_spec = *arg == ':' ? arg + 1 : "";
            break;
        case 'c':
        case 'p':
            if (*(++arg) == ':')
                *index = strtol(++arg, NULL, 0);
            break;
        default:
            av_log(NULL, AV_LOG_FATAL, "Invalid metadata type %c.\n", *arg);
            exit_program(1);
        }
    } else
        *type = 'g';
}

int fftools_copy_metadata(char *outspec, char *inspec, AVFormatContext *oc, AVFormatContext *ic, OptionsContext *o)
{
    AVDictionary **meta_in = NULL;
    AVDictionary **meta_out = NULL;
    int i, ret = 0;
    char type_in, type_out;
    const char *istream_spec = NULL, *ostream_spec = NULL;
    int idx_in = 0, idx_out = 0;

    parse_meta_type(inspec,  &type_in,  &idx_in,  &istream_spec);
    parse_meta_type(outspec, &type_out, &idx_out, &ostream_spec);

    if (!ic) {
        if (type_out == 'g' || !*outspec)
            o->metadata_global_manual = 1;
        if (type_out == 's' || !*outspec)
            o->metadata_streams_manual = 1;
        if (type_out == 'c' || !*outspec)
            o->metadata_chapters_manual = 1;
        return 0;
    }

    if (type_in == 'g' || type_out == 'g')
        o->metadata_global_manual = 1;
    if (type_in == 's' || type_out == 's')
        o->metadata_streams_manual = 1;
    if (type_in == 'c' || type_out == 'c')
        o->metadata_chapters_manual = 1;

    /* ic is NULL when just disabling automatic mappings */
    if (!ic)
        return 0;

#define METADATA_CHECK_INDEX(index, nb_elems, desc)\
    if ((index) < 0 || (index) >= (nb_elems)) {\
        av_log(NULL, AV_LOG_FATAL, "Invalid %s index %d while processing metadata maps.\n",\
                (desc), (index));\
        exit_program(1);\
    }

#define SET_DICT(type, meta, context, index)\
        switch (type) {\
        case 'g':\
            meta = &context->metadata;\
            break;\
        case 'c':\
            METADATA_CHECK_INDEX(index, context->nb_chapters, "chapter")\
            meta = &context->chapters[index]->metadata;\
            break;\
        case 'p':\
            METADATA_CHECK_INDEX(index, context->nb_programs, "program")\
            meta = &context->programs[index]->metadata;\
            break;\
        case 's':\
            break; /* handled separately below */ \
        default: av_assert0(0);\
        }\

    SET_DICT(type_in, meta_in, ic, idx_in);
    SET_DICT(type_out, meta_out, oc, idx_out);

    /* for input streams choose first matching stream */
    if (type_in == 's') {
        for (i = 0; i < ic->nb_streams; i++) {
            if ((ret = check_stream_specifier(ic, ic->streams[i], istream_spec)) > 0) {
                meta_in = &ic->streams[i]->metadata;
                break;
            } else if (ret < 0)
                exit_program(1);
        }
        if (!meta_in) {
            av_log(NULL, AV_LOG_FATAL, "Stream specifier %s does not match  any streams.\n", istream_spec);
            exit_program(1);
        }
    }

    if (type_out == 's') {
        for (i = 0; i < oc->nb_streams; i++) {
            if ((ret = check_stream_specifier(oc, oc->streams[i], ostream_spec)) > 0) {
                meta_out = &oc->streams[i]->metadata;
                av_dict_copy(meta_out, *meta_in, AV_DICT_DONT_OVERWRITE);
            } else if (ret < 0)
                exit_program(1);
        }
    } else
        av_dict_copy(meta_out, *meta_in, AV_DICT_DONT_OVERWRITE);

    return 0;
}

int opt_recording_timestamp(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    char buf[128];
    int64_t recording_timestamp = parse_time_or_die(opt, arg, 0) / 1E6;
    struct tm time = *gmtime((time_t*)&recording_timestamp);
    if (!strftime(buf, sizeof(buf), "creation_time=%Y-%m-%dT%H:%M:%S%z", &time))
        return -1;
    parse_option(o, "metadata", buf, ffmpeg_options);

    av_log(NULL, AV_LOG_WARNING, "%s is deprecated, set the 'creation_time' metadata "
                                 "tag instead.\n", opt);
    return 0;
}

const AVCodec *find_codec_or_die(const char *name, enum AVMediaType type, int encoder)
{
    const AVCodecDescriptor *desc;
    const char *codec_string = encoder ? "encoder" : "decoder";
    const AVCodec *codec;

    codec = encoder ?
        avcodec_find_encoder_by_name(name) :
        avcodec_find_decoder_by_name(name);

    if (!codec && (desc = avcodec_descriptor_get_by_name(name))) {
        codec = encoder ? avcodec_find_encoder(desc->id) :
                          avcodec_find_decoder(desc->id);
        if (codec)
            av_log(NULL, AV_LOG_VERBOSE, "Matched %s '%s' for codec '%s'.\n",
                   codec_string, codec->name, desc->name);
    }

    if (!codec) {
        av_log(NULL, AV_LOG_FATAL, "Unknown %s '%s'\n", codec_string, name);
        exit_program(1);
    }
    if (codec->type != type && !recast_media) {
        av_log(NULL, AV_LOG_FATAL, "Invalid %s type '%s'\n", codec_string, name);
        exit_program(1);
    }
    return codec;
}

const AVCodec *choose_decoder(OptionsContext *o, AVFormatContext *s, AVStream *st)
{
    char *codec_name = NULL;

    MATCH_PER_STREAM_OPT(codec_names, str, codec_name, s, st);
    if (codec_name) {
        const AVCodec *codec = find_codec_or_die(codec_name, st->codecpar->codec_type, 0);
        st->codecpar->codec_id = codec->id;
        if (recast_media && st->codecpar->codec_type != codec->type)
            st->codecpar->codec_type = codec->type;
        return codec;
    } else
        return avcodec_find_decoder(st->codecpar->codec_id);
}

/* Add all the streams from the given input file to the global
 * list of input streams. */
void add_input_streams(OptionsContext *o, AVFormatContext *ic)
{
    int i, ret;

    for (i = 0; i < ic->nb_streams; i++) {
        AVStream *st = ic->streams[i];
        AVCodecParameters *par = st->codecpar;
        InputStream *ist;
        char *framerate = NULL, *hwaccel_device = NULL;
        const char *hwaccel = NULL;
        char *hwaccel_output_format = NULL;
        char *codec_tag = NULL;
        char *next;
        char *discard_str = NULL;
        const AVClass *cc = avcodec_get_class();
        const AVOption *discard_opt = av_opt_find(&cc, "skip_frame", NULL,
                                                  0, AV_OPT_SEARCH_FAKE_OBJ);

        ist = ALLOC_ARRAY_ELEM(input_streams, nb_input_streams);
        ist->st = st;
        ist->file_index = nb_input_files;
        ist->discard = 1;
        st->discard  = AVDISCARD_ALL;
        ist->nb_samples = 0;
        ist->first_dts = AV_NOPTS_VALUE;
        ist->min_pts = INT64_MAX;
        ist->max_pts = INT64_MIN;

        ist->ts_scale = 1.0;
        MATCH_PER_STREAM_OPT(ts_scale, dbl, ist->ts_scale, ic, st);

        ist->autorotate = 1;
        MATCH_PER_STREAM_OPT(autorotate, i, ist->autorotate, ic, st);

        MATCH_PER_STREAM_OPT(codec_tags, str, codec_tag, ic, st);
        if (codec_tag) {
            uint32_t tag = strtol(codec_tag, &next, 0);
            if (*next)
                tag = AV_RL32(codec_tag);
            st->codecpar->codec_tag = tag;
        }

        ist->dec = choose_decoder(o, ic, st);
        ist->decoder_opts = filter_codec_opts(o->g->codec_opts, ist->st->codecpar->codec_id, ic, st, ist->dec);

        ist->reinit_filters = -1;
        MATCH_PER_STREAM_OPT(reinit_filters, i, ist->reinit_filters, ic, st);

        MATCH_PER_STREAM_OPT(discard, str, discard_str, ic, st);
        ist->user_set_discard = AVDISCARD_NONE;

        if ((o->video_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) ||
            (o->audio_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) ||
            (o->subtitle_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) ||
            (o->data_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_DATA))
                ist->user_set_discard = AVDISCARD_ALL;

        if (discard_str && av_opt_eval_int(&cc, discard_opt, discard_str, &ist->user_set_discard) < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error parsing discard %s.\n",
                    discard_str);
            exit_program(1);
        }

        ist->filter_in_rescale_delta_last = AV_NOPTS_VALUE;
        ist->prev_pkt_pts = AV_NOPTS_VALUE;

        ist->dec_ctx = avcodec_alloc_context3(ist->dec);
        if (!ist->dec_ctx) {
            av_log(NULL, AV_LOG_ERROR, "Error allocating the decoder context.\n");
            exit_program(1);
        }

        ret = avcodec_parameters_to_context(ist->dec_ctx, par);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error initializing the decoder context.\n");
            exit_program(1);
        }

        ist->decoded_frame = av_frame_alloc();
        if (!ist->decoded_frame)
            exit_program(1);

        ist->pkt = av_packet_alloc();
        if (!ist->pkt)
            exit_program(1);

        if (o->bitexact)
            ist->dec_ctx->flags |= AV_CODEC_FLAG_BITEXACT;

        switch (par->codec_type) {
        case AVMEDIA_TYPE_VIDEO:
            if(!ist->dec)
                ist->dec = avcodec_find_decoder(par->codec_id);

            // avformat_find_stream_info() doesn't set this for us anymore.
            ist->dec_ctx->framerate = st->avg_frame_rate;

            MATCH_PER_STREAM_OPT(frame_rates, str, framerate, ic, st);
            if (framerate && av_parse_video_rate(&ist->framerate,
                                                 framerate) < 0) {
                av_log(NULL, AV_LOG_ERROR, "Error parsing framerate %s.\n",
                       framerate);
                exit_program(1);
            }

            ist->top_field_first = -1;
            MATCH_PER_STREAM_OPT(top_field_first, i, ist->top_field_first, ic, st);

            MATCH_PER_STREAM_OPT(hwaccels, str, hwaccel, ic, st);
            MATCH_PER_STREAM_OPT(hwaccel_output_formats, str,
                                 hwaccel_output_format, ic, st);

            if (!hwaccel_output_format && hwaccel && !strcmp(hwaccel, "cuvid")) {
                av_log(NULL, AV_LOG_WARNING,
                    "WARNING: defaulting hwaccel_output_format to cuda for compatibility "
                    "with old commandlines. This behaviour is DEPRECATED and will be removed "
                    "in the future. Please explicitly set \"-hwaccel_output_format cuda\".\n");
                ist->hwaccel_output_format = AV_PIX_FMT_CUDA;
            } else if (!hwaccel_output_format && hwaccel && !strcmp(hwaccel, "qsv")) {
                av_log(NULL, AV_LOG_WARNING,
                    "WARNING: defaulting hwaccel_output_format to qsv for compatibility "
                    "with old commandlines. This behaviour is DEPRECATED and will be removed "
                    "in the future. Please explicitly set \"-hwaccel_output_format qsv\".\n");
                ist->hwaccel_output_format = AV_PIX_FMT_QSV;
            } else if (hwaccel_output_format) {
                ist->hwaccel_output_format = av_get_pix_fmt(hwaccel_output_format);
                if (ist->hwaccel_output_format == AV_PIX_FMT_NONE) {
                    av_log(NULL, AV_LOG_FATAL, "Unrecognised hwaccel output "
                           "format: %s", hwaccel_output_format);
                }
            } else {
                ist->hwaccel_output_format = AV_PIX_FMT_NONE;
            }

            if (hwaccel) {
                // The NVDEC hwaccels use a CUDA device, so remap the name here.
                if (!strcmp(hwaccel, "nvdec") || !strcmp(hwaccel, "cuvid"))
                    hwaccel = "cuda";

                if (!strcmp(hwaccel, "none"))
                    ist->hwaccel_id = HWACCEL_NONE;
                else if (!strcmp(hwaccel, "auto"))
                    ist->hwaccel_id = HWACCEL_AUTO;
                else {
                    enum AVHWDeviceType type = av_hwdevice_find_type_by_name(hwaccel);
                    if (type != AV_HWDEVICE_TYPE_NONE) {
                        ist->hwaccel_id = HWACCEL_GENERIC;
                        ist->hwaccel_device_type = type;
                    }

                    if (!ist->hwaccel_id) {
                        av_log(NULL, AV_LOG_FATAL, "Unrecognized hwaccel: %s.\n",
                               hwaccel);
                        av_log(NULL, AV_LOG_FATAL, "Supported hwaccels: ");
                        type = AV_HWDEVICE_TYPE_NONE;
                        while ((type = av_hwdevice_iterate_types(type)) !=
                               AV_HWDEVICE_TYPE_NONE)
                            av_log(NULL, AV_LOG_FATAL, "%s ",
                                   av_hwdevice_get_type_name(type));
                        av_log(NULL, AV_LOG_FATAL, "\n");
                        exit_program(1);
                    }
                }
            }

            MATCH_PER_STREAM_OPT(hwaccel_devices, str, hwaccel_device, ic, st);
            if (hwaccel_device) {
                ist->hwaccel_device = av_strdup(hwaccel_device);
                if (!ist->hwaccel_device)
                    exit_program(1);
            }

            ist->hwaccel_pix_fmt = AV_PIX_FMT_NONE;

            break;
        case AVMEDIA_TYPE_AUDIO:
            ist->guess_layout_max = INT_MAX;
            MATCH_PER_STREAM_OPT(guess_layout_max, i, ist->guess_layout_max, ic, st);
            guess_input_channel_layout(ist);
            break;
        case AVMEDIA_TYPE_DATA:
        case AVMEDIA_TYPE_SUBTITLE: {
            char *canvas_size = NULL;
            if(!ist->dec)
                ist->dec = avcodec_find_decoder(par->codec_id);
            MATCH_PER_STREAM_OPT(fix_sub_duration, i, ist->fix_sub_duration, ic, st);
            MATCH_PER_STREAM_OPT(canvas_sizes, str, canvas_size, ic, st);
            if (canvas_size &&
                av_parse_video_size(&ist->dec_ctx->width, &ist->dec_ctx->height, canvas_size) < 0) {
                av_log(NULL, AV_LOG_FATAL, "Invalid canvas size: %s.\n", canvas_size);
                exit_program(1);
            }
            break;
        }
        case AVMEDIA_TYPE_ATTACHMENT:
        case AVMEDIA_TYPE_UNKNOWN:
            break;
        default:
            abort();
        }

        ret = avcodec_parameters_from_context(par, ist->dec_ctx);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error initializing the decoder context.\n");
            exit_program(1);
        }
    }
}

void assert_file_overwrite(const char *filename)
{
    const char *proto_name = avio_find_protocol_name(filename);

    if (file_overwrite && no_file_overwrite) {
        av_log(NULL, AV_LOG_FATAL, "Error, both -y and -n supplied. Exiting.\n");
        exit_program(1);
    }

    if (!file_overwrite) {
        if (proto_name && !strcmp(proto_name, "file") && avio_check(filename, 0) == 0) {
            if (stdin_interaction && !no_file_overwrite) {
                av_log(NULL, AV_LOG_FATAL, "File '%s' already exists. Overwrite? [y/N] ", filename);
                term_exit();
                signal(SIGINT, SIG_DFL);
                if (!read_yesno()) {
                    av_log(NULL, AV_LOG_FATAL, "Not overwriting - exiting\n");
                    exit_program(1);
                }
                term_init();
            }
            else {
                av_log(NULL, AV_LOG_FATAL, "File '%s' already exists. Exiting.\n", filename);
                exit_program(1);
            }
        }
    }

    if (proto_name && !strcmp(proto_name, "file")) {
        for (int i = 0; i < nb_input_files; i++) {
             InputFile *file = input_files[i];
             if (file->ctx->iformat->flags & AVFMT_NOFILE)
                 continue;
             if (!strcmp(filename, file->ctx->url)) {
                 av_log(NULL, AV_LOG_FATAL, "Output %s same as Input #%d - exiting\n", filename, i);
                 av_log(NULL, AV_LOG_WARNING, "FFmpeg cannot edit existing files in-place.\n");
                 exit_program(1);
             }
        }
    }
}

void dump_attachment(AVStream *st, const char *filename)
{
    int ret;
    AVIOContext *out = NULL;
    const AVDictionaryEntry *e;

    if (!st->codecpar->extradata_size) {
        av_log(NULL, AV_LOG_WARNING, "No extradata to dump in stream #%d:%d.\n",
               nb_input_files - 1, st->index);
        return;
    }
    if (!*filename && (e = av_dict_get(st->metadata, "filename", NULL, 0)))
        filename = e->value;
    if (!*filename) {
        av_log(NULL, AV_LOG_FATAL, "No filename specified and no 'filename' tag"
               "in stream #%d:%d.\n", nb_input_files - 1, st->index);
        exit_program(1);
    }

    assert_file_overwrite(filename);

    if ((ret = avio_open2(&out, filename, AVIO_FLAG_WRITE, &int_cb, NULL)) < 0) {
        av_log(NULL, AV_LOG_FATAL, "Could not open file %s for writing.\n",
               filename);
        exit_program(1);
    }

    avio_write(out, st->codecpar->extradata, st->codecpar->extradata_size);
    avio_flush(out);
    avio_close(out);
}

int open_input_file(OptionsContext *o, const char *filename)
{
    InputFile *f;
    AVFormatContext *ic;
    const AVInputFormat *file_iformat = NULL;
    int err, i, ret;
    int64_t timestamp;
    AVDictionary *unused_opts = NULL;
    const AVDictionaryEntry *e = NULL;
    char *   video_codec_name = NULL;
    char *   audio_codec_name = NULL;
    char *subtitle_codec_name = NULL;
    char *    data_codec_name = NULL;
    int scan_all_pmts_set = 0;

    if (o->stop_time != INT64_MAX && o->recording_time != INT64_MAX) {
        o->stop_time = INT64_MAX;
        av_log(NULL, AV_LOG_WARNING, "-t and -to cannot be used together; using -t.\n");
    }

    if (o->stop_time != INT64_MAX && o->recording_time == INT64_MAX) {
        int64_t start_time = o->start_time == AV_NOPTS_VALUE ? 0 : o->start_time;
        if (o->stop_time <= start_time) {
            av_log(NULL, AV_LOG_ERROR, "-to value smaller than -ss; aborting.\n");
            exit_program(1);
        } else {
            o->recording_time = o->stop_time - start_time;
        }
    }

    if (o->format) {
        if (!(file_iformat = av_find_input_format(o->format))) {
            av_log(NULL, AV_LOG_FATAL, "Unknown input format: '%s'\n", o->format);
            exit_program(1);
        }
    }

    if (!strcmp(filename, "-"))
        filename = "pipe:";

    stdin_interaction &= strncmp(filename, "pipe:", 5) &&
                         strcmp(filename, "/dev/stdin");

    /* get default parameters from command line */
    ic = avformat_alloc_context();
    if (!ic) {
        print_error(filename, AVERROR(ENOMEM));
        exit_program(1);
    }
    if (o->nb_audio_sample_rate) {
        av_dict_set_int(&o->g->format_opts, "sample_rate", o->audio_sample_rate[o->nb_audio_sample_rate - 1].u.i, 0);
    }
    if (o->nb_audio_channels) {
        const AVClass *priv_class;
        if (file_iformat && (priv_class = file_iformat->priv_class) &&
            av_opt_find(&priv_class, "ch_layout", NULL, 0,
                        AV_OPT_SEARCH_FAKE_OBJ)) {
            char buf[32];
            snprintf(buf, sizeof(buf), "%dC", o->audio_channels[o->nb_audio_channels - 1].u.i);
            av_dict_set(&o->g->format_opts, "ch_layout", buf, 0);
        }
    }
    if (o->nb_audio_ch_layouts) {
        const AVClass *priv_class;
        if (file_iformat && (priv_class = file_iformat->priv_class) &&
            av_opt_find(&priv_class, "ch_layout", NULL, 0,
                        AV_OPT_SEARCH_FAKE_OBJ)) {
            av_dict_set(&o->g->format_opts, "ch_layout", o->audio_ch_layouts[o->nb_audio_ch_layouts - 1].u.str, 0);
        }
    }
    if (o->nb_frame_rates) {
        const AVClass *priv_class;
        /* set the format-level framerate option;
         * this is important for video grabbers, e.g. x11 */
        if (file_iformat && (priv_class = file_iformat->priv_class) &&
            av_opt_find(&priv_class, "framerate", NULL, 0,
                        AV_OPT_SEARCH_FAKE_OBJ)) {
            av_dict_set(&o->g->format_opts, "framerate",
                        o->frame_rates[o->nb_frame_rates - 1].u.str, 0);
        }
    }
    if (o->nb_frame_sizes) {
        av_dict_set(&o->g->format_opts, "video_size", o->frame_sizes[o->nb_frame_sizes - 1].u.str, 0);
    }
    if (o->nb_frame_pix_fmts)
        av_dict_set(&o->g->format_opts, "pixel_format", o->frame_pix_fmts[o->nb_frame_pix_fmts - 1].u.str, 0);

    MATCH_PER_TYPE_OPT(codec_names, str,    video_codec_name, ic, "v");
    MATCH_PER_TYPE_OPT(codec_names, str,    audio_codec_name, ic, "a");
    MATCH_PER_TYPE_OPT(codec_names, str, subtitle_codec_name, ic, "s");
    MATCH_PER_TYPE_OPT(codec_names, str,     data_codec_name, ic, "d");

    if (video_codec_name)
        ic->video_codec    = find_codec_or_die(video_codec_name   , AVMEDIA_TYPE_VIDEO   , 0);
    if (audio_codec_name)
        ic->audio_codec    = find_codec_or_die(audio_codec_name   , AVMEDIA_TYPE_AUDIO   , 0);
    if (subtitle_codec_name)
        ic->subtitle_codec = find_codec_or_die(subtitle_codec_name, AVMEDIA_TYPE_SUBTITLE, 0);
    if (data_codec_name)
        ic->data_codec     = find_codec_or_die(data_codec_name    , AVMEDIA_TYPE_DATA    , 0);

    ic->video_codec_id     = video_codec_name    ? ic->video_codec->id    : AV_CODEC_ID_NONE;
    ic->audio_codec_id     = audio_codec_name    ? ic->audio_codec->id    : AV_CODEC_ID_NONE;
    ic->subtitle_codec_id  = subtitle_codec_name ? ic->subtitle_codec->id : AV_CODEC_ID_NONE;
    ic->data_codec_id      = data_codec_name     ? ic->data_codec->id     : AV_CODEC_ID_NONE;

    ic->flags |= AVFMT_FLAG_NONBLOCK;
    if (o->bitexact)
        ic->flags |= AVFMT_FLAG_BITEXACT;
    ic->interrupt_callback = int_cb;

    if (!av_dict_get(o->g->format_opts, "scan_all_pmts", NULL, AV_DICT_MATCH_CASE)) {
        av_dict_set(&o->g->format_opts, "scan_all_pmts", "1", AV_DICT_DONT_OVERWRITE);
        scan_all_pmts_set = 1;
    }
    /* open the input file with generic avformat function */
    err = avformat_open_input(&ic, filename, file_iformat, &o->g->format_opts);
    if (err < 0) {
        print_error(filename, err);
        if (err == AVERROR_PROTOCOL_NOT_FOUND)
            av_log(NULL, AV_LOG_ERROR, "Did you mean file:%s?\n", filename);
        exit_program(1);
    }
    if (scan_all_pmts_set)
        av_dict_set(&o->g->format_opts, "scan_all_pmts", NULL, AV_DICT_MATCH_CASE);
    remove_avoptions(&o->g->format_opts, o->g->codec_opts);
    assert_avoptions(o->g->format_opts);

    /* apply forced codec ids */
    for (i = 0; i < ic->nb_streams; i++)
        choose_decoder(o, ic, ic->streams[i]);

    if (find_stream_info) {
        AVDictionary **opts = setup_find_stream_info_opts(ic, o->g->codec_opts);
        int orig_nb_streams = ic->nb_streams;

        /* If not enough info to get the stream parameters, we decode the
           first frames to get it. (used in mpeg case for example) */
        ret = avformat_find_stream_info(ic, opts);

        for (i = 0; i < orig_nb_streams; i++)
            av_dict_free(&opts[i]);
        av_freep(&opts);

        if (ret < 0) {
            av_log(NULL, AV_LOG_FATAL, "%s: could not find codec parameters\n", filename);
            if (ic->nb_streams == 0) {
                avformat_close_input(&ic);
                exit_program(1);
            }
        }
    }

    if (o->start_time != AV_NOPTS_VALUE && o->start_time_eof != AV_NOPTS_VALUE) {
        av_log(NULL, AV_LOG_WARNING, "Cannot use -ss and -sseof both, using -ss for %s\n", filename);
        o->start_time_eof = AV_NOPTS_VALUE;
    }

    if (o->start_time_eof != AV_NOPTS_VALUE) {
        if (o->start_time_eof >= 0) {
            av_log(NULL, AV_LOG_ERROR, "-sseof value must be negative; aborting\n");
            exit_program(1);
        }
        if (ic->duration > 0) {
            o->start_time = o->start_time_eof + ic->duration;
            if (o->start_time < 0) {
                av_log(NULL, AV_LOG_WARNING, "-sseof value seeks to before start of file %s; ignored\n", filename);
                o->start_time = AV_NOPTS_VALUE;
            }
        } else
            av_log(NULL, AV_LOG_WARNING, "Cannot use -sseof, duration of %s not known\n", filename);
    }
    timestamp = (o->start_time == AV_NOPTS_VALUE) ? 0 : o->start_time;
    /* add the stream start time */
    if (!o->seek_timestamp && ic->start_time != AV_NOPTS_VALUE)
        timestamp += ic->start_time;

    /* if seeking requested, we execute it */
    if (o->start_time != AV_NOPTS_VALUE) {
        int64_t seek_timestamp = timestamp;

        if (!(ic->iformat->flags & AVFMT_SEEK_TO_PTS)) {
            int dts_heuristic = 0;
            for (i=0; i<ic->nb_streams; i++) {
                const AVCodecParameters *par = ic->streams[i]->codecpar;
                if (par->video_delay) {
                    dts_heuristic = 1;
                    break;
                }
            }
            if (dts_heuristic) {
                seek_timestamp -= 3*AV_TIME_BASE / 23;
            }
        }
        ret = avformat_seek_file(ic, -1, INT64_MIN, seek_timestamp, seek_timestamp, 0);
        if (ret < 0) {
            av_log(NULL, AV_LOG_WARNING, "%s: could not seek to position %0.3f\n",
                   filename, (double)timestamp / AV_TIME_BASE);
        }
    }

    /* update the current parameters so that they match the one of the input stream */
    add_input_streams(o, ic);

    /* dump the file content */
    av_dump_format(ic, nb_input_files, filename, 0);

    f = ALLOC_ARRAY_ELEM(input_files, nb_input_files);

    f->ctx        = ic;
    f->ist_index  = nb_input_streams - ic->nb_streams;
    f->start_time = o->start_time;
    f->recording_time = o->recording_time;
    f->input_sync_ref = o->input_sync_ref;
    f->input_ts_offset = o->input_ts_offset;
    f->ts_offset  = o->input_ts_offset - (copy_ts ? (start_at_zero && ic->start_time != AV_NOPTS_VALUE ? ic->start_time : 0) : timestamp);
    f->nb_streams = ic->nb_streams;
    f->rate_emu   = o->rate_emu;
    f->accurate_seek = o->accurate_seek;
    f->loop = o->loop;
    f->duration = 0;
    f->time_base = (AVRational){ 1, 1 };

    f->readrate = o->readrate ? o->readrate : 0.0;
    if (f->readrate < 0.0f) {
        av_log(NULL, AV_LOG_ERROR, "Option -readrate for Input #%d is %0.3f; it must be non-negative.\n", nb_input_files, f->readrate);
        exit_program(1);
    }
    if (f->readrate && f->rate_emu) {
        av_log(NULL, AV_LOG_WARNING, "Both -readrate and -re set for Input #%d. Using -readrate %0.3f.\n", nb_input_files, f->readrate);
        f->rate_emu = 0;
    }

    f->pkt = av_packet_alloc();
    if (!f->pkt)
        exit_program(1);
#if HAVE_THREADS
    f->thread_queue_size = o->thread_queue_size;
#endif

    /* check if all codec options have been used */
    unused_opts = strip_specifiers(o->g->codec_opts);
    for (i = f->ist_index; i < nb_input_streams; i++) {
        e = NULL;
        while ((e = av_dict_get(input_streams[i]->decoder_opts, "", e,
                                AV_DICT_IGNORE_SUFFIX)))
            av_dict_set(&unused_opts, e->key, NULL, 0);
    }

    e = NULL;
    while ((e = av_dict_get(unused_opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
        const AVClass *class = avcodec_get_class();
        const AVOption *option = av_opt_find(&class, e->key, NULL, 0,
                                             AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
        const AVClass *fclass = avformat_get_class();
        const AVOption *foption = av_opt_find(&fclass, e->key, NULL, 0,
                                             AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
        if (!option || foption)
            continue;


        if (!(option->flags & AV_OPT_FLAG_DECODING_PARAM)) {
            av_log(NULL, AV_LOG_ERROR, "Codec AVOption %s (%s) specified for "
                   "input file #%d (%s) is not a decoding option.\n", e->key,
                   option->help ? option->help : "", nb_input_files - 1,
                   filename);
            exit_program(1);
        }

        av_log(NULL, AV_LOG_WARNING, "Codec AVOption %s (%s) specified for "
               "input file #%d (%s) has not been used for any stream. The most "
               "likely reason is either wrong type (e.g. a video option with "
               "no video streams) or that it is a private option of some decoder "
               "which was not actually used for any stream.\n", e->key,
               option->help ? option->help : "", nb_input_files - 1, filename);
    }
    av_dict_free(&unused_opts);

    for (i = 0; i < o->nb_dump_attachment; i++) {
        int j;

        for (j = 0; j < ic->nb_streams; j++) {
            AVStream *st = ic->streams[j];

            if (check_stream_specifier(ic, st, o->dump_attachment[i].specifier) == 1)
                dump_attachment(st, o->dump_attachment[i].u.str);
        }
    }

    input_stream_potentially_available = 1;

    return 0;
}

char *get_line(AVIOContext *s, AVBPrint *bprint)
{
    char c;

    while ((c = avio_r8(s)) && c != '\n')
        av_bprint_chars(bprint, c, 1);

    if (!av_bprint_is_complete(bprint)) {
        av_log(NULL, AV_LOG_FATAL, "Could not alloc buffer for reading preset.\n");
        exit_program(1);
    }
    return bprint->str;
}

int get_preset_file_2(const char *preset_name, const char *codec_name, AVIOContext **s)
{
    int i, ret = -1;
    char filename[1000];
    char *env_avconv_datadir = getenv_utf8("AVCONV_DATADIR");
    char *env_home = getenv_utf8("HOME");
    const char *base[3] = { env_avconv_datadir,
                            env_home,
                            AVCONV_DATADIR,
                            };

    for (i = 0; i < FF_ARRAY_ELEMS(base) && ret < 0; i++) {
        if (!base[i])
            continue;
        if (codec_name) {
            snprintf(filename, sizeof(filename), "%s%s/%s-%s.avpreset", base[i],
                     i != 1 ? "" : "/.avconv", codec_name, preset_name);
            ret = avio_open2(s, filename, AVIO_FLAG_READ, &int_cb, NULL);
        }
        if (ret < 0) {
            snprintf(filename, sizeof(filename), "%s%s/%s.avpreset", base[i],
                     i != 1 ? "" : "/.avconv", preset_name);
            ret = avio_open2(s, filename, AVIO_FLAG_READ, &int_cb, NULL);
        }
    }
    freeenv_utf8(env_home);
    freeenv_utf8(env_avconv_datadir);
    return ret;
}

int choose_encoder(OptionsContext *o, AVFormatContext *s, OutputStream *ost)
{
    enum AVMediaType type = ost->st->codecpar->codec_type;
    char *codec_name = NULL;

    if (type == AVMEDIA_TYPE_VIDEO || type == AVMEDIA_TYPE_AUDIO || type == AVMEDIA_TYPE_SUBTITLE) {
        MATCH_PER_STREAM_OPT(codec_names, str, codec_name, s, ost->st);
        if (!codec_name) {
            ost->st->codecpar->codec_id = av_guess_codec(s->oformat, NULL, s->url,
                                                         NULL, ost->st->codecpar->codec_type);
            ost->enc = avcodec_find_encoder(ost->st->codecpar->codec_id);
            if (!ost->enc) {
                av_log(NULL, AV_LOG_FATAL, "Automatic encoder selection failed for "
                       "output stream #%d:%d. Default encoder for format %s (codec %s) is "
                       "probably disabled. Please choose an encoder manually.\n",
                       ost->file_index, ost->index, s->oformat->name,
                       avcodec_get_name(ost->st->codecpar->codec_id));
                return AVERROR_ENCODER_NOT_FOUND;
            }
        } else if (!strcmp(codec_name, "copy"))
            ost->stream_copy = 1;
        else {
            ost->enc = find_codec_or_die(codec_name, ost->st->codecpar->codec_type, 1);
            ost->st->codecpar->codec_id = ost->enc->id;
        }
        ost->encoding_needed = !ost->stream_copy;
    } else {
        /* no encoding supported for other media types */
        ost->stream_copy     = 1;
        ost->encoding_needed = 0;
    }

    return 0;
}

OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, enum AVMediaType type, int source_index)
{
    OutputStream *ost;
    AVStream *st = avformat_new_stream(oc, NULL);
    int idx      = oc->nb_streams - 1, ret = 0;
    const char *bsfs = NULL, *time_base = NULL;
    char *next, *codec_tag = NULL;
    double qscale = -1;
    int i;

    if (!st) {
        av_log(NULL, AV_LOG_FATAL, "Could not alloc stream.\n");
        exit_program(1);
    }

    if (oc->nb_streams - 1 < o->nb_streamid_map)
        st->id = o->streamid_map[oc->nb_streams - 1];

    ost = ALLOC_ARRAY_ELEM(output_streams, nb_output_streams);

    ost->file_index = nb_output_files - 1;
    ost->index      = idx;
    ost->st         = st;
    ost->forced_kf_ref_pts = AV_NOPTS_VALUE;
    st->codecpar->codec_type = type;

    ret = choose_encoder(o, oc, ost);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error selecting an encoder for stream "
               "%d:%d\n", ost->file_index, ost->index);
        exit_program(1);
    }

    ost->enc_ctx = avcodec_alloc_context3(ost->enc);
    if (!ost->enc_ctx) {
        av_log(NULL, AV_LOG_ERROR, "Error allocating the encoding context.\n");
        exit_program(1);
    }
    ost->enc_ctx->codec_type = type;

    ost->ref_par = avcodec_parameters_alloc();
    if (!ost->ref_par) {
        av_log(NULL, AV_LOG_ERROR, "Error allocating the encoding parameters.\n");
        exit_program(1);
    }

    ost->filtered_frame = av_frame_alloc();
    if (!ost->filtered_frame)
        exit_program(1);

    ost->pkt = av_packet_alloc();
    if (!ost->pkt)
        exit_program(1);

    if (ost->enc) {
        AVIOContext *s = NULL;
        char *buf = NULL, *arg = NULL, *preset = NULL;

        ost->encoder_opts  = filter_codec_opts(o->g->codec_opts, ost->enc->id, oc, st, ost->enc);

        MATCH_PER_STREAM_OPT(presets, str, preset, oc, st);
        ost->autoscale = 1;
        MATCH_PER_STREAM_OPT(autoscale, i, ost->autoscale, oc, st);
        if (preset && (!(ret = get_preset_file_2(preset, ost->enc->name, &s)))) {
            AVBPrint bprint;
            av_bprint_init(&bprint, 0, AV_BPRINT_SIZE_UNLIMITED);
            do  {
                av_bprint_clear(&bprint);
                buf = get_line(s, &bprint);
                if (!buf[0] || buf[0] == '#')
                    continue;
                if (!(arg = strchr(buf, '='))) {
                    av_log(NULL, AV_LOG_FATAL, "Invalid line found in the preset file.\n");
                    exit_program(1);
                }
                *arg++ = 0;
                av_dict_set(&ost->encoder_opts, buf, arg, AV_DICT_DONT_OVERWRITE);
            } while (!s->eof_reached);
            av_bprint_finalize(&bprint, NULL);
            avio_closep(&s);
        }
        if (ret) {
            av_log(NULL, AV_LOG_FATAL,
                   "Preset %s specified for stream %d:%d, but could not be opened.\n",
                   preset, ost->file_index, ost->index);
            exit_program(1);
        }
    } else {
        ost->encoder_opts = filter_codec_opts(o->g->codec_opts, AV_CODEC_ID_NONE, oc, st, NULL);
    }


    if (o->bitexact)
        ost->enc_ctx->flags |= AV_CODEC_FLAG_BITEXACT;

    MATCH_PER_STREAM_OPT(time_bases, str, time_base, oc, st);
    if (time_base) {
        AVRational q;
        if (av_parse_ratio(&q, time_base, INT_MAX, 0, NULL) < 0 ||
            q.num <= 0 || q.den <= 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid time base: %s\n", time_base);
            exit_program(1);
        }
        st->time_base = q;
    }

    MATCH_PER_STREAM_OPT(enc_time_bases, str, time_base, oc, st);
    if (time_base) {
        AVRational q;
        if (av_parse_ratio(&q, time_base, INT_MAX, 0, NULL) < 0 ||
            q.den <= 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid time base: %s\n", time_base);
            exit_program(1);
        }
        ost->enc_timebase = q;
    }

    ost->max_frames = INT64_MAX;
    MATCH_PER_STREAM_OPT(max_frames, i64, ost->max_frames, oc, st);
    for (i = 0; i<o->nb_max_frames; i++) {
        char *p = o->max_frames[i].specifier;
        if (!*p && type != AVMEDIA_TYPE_VIDEO) {
            av_log(NULL, AV_LOG_WARNING, "Applying unspecific -frames to non video streams, maybe you meant -vframes ?\n");
            break;
        }
    }

    ost->copy_prior_start = -1;
    MATCH_PER_STREAM_OPT(copy_prior_start, i, ost->copy_prior_start, oc ,st);

    MATCH_PER_STREAM_OPT(bitstream_filters, str, bsfs, oc, st);
    if (bsfs && *bsfs) {
        ret = av_bsf_list_parse_str(bsfs, &ost->bsf_ctx);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error parsing bitstream filter sequence '%s': %s\n", bsfs, av_err2str(ret));
            exit_program(1);
        }
    }

    MATCH_PER_STREAM_OPT(codec_tags, str, codec_tag, oc, st);
    if (codec_tag) {
        uint32_t tag = strtol(codec_tag, &next, 0);
        if (*next)
            tag = AV_RL32(codec_tag);
        ost->st->codecpar->codec_tag =
        ost->enc_ctx->codec_tag = tag;
    }

    MATCH_PER_STREAM_OPT(qscale, dbl, qscale, oc, st);
    if (qscale >= 0) {
        ost->enc_ctx->flags |= AV_CODEC_FLAG_QSCALE;
        ost->enc_ctx->global_quality = FF_QP2LAMBDA * qscale;
    }

    MATCH_PER_STREAM_OPT(disposition, str, ost->disposition, oc, st);
    ost->disposition = av_strdup(ost->disposition);

    ost->max_muxing_queue_size = 128;
    MATCH_PER_STREAM_OPT(max_muxing_queue_size, i, ost->max_muxing_queue_size, oc, st);

    ost->muxing_queue_data_size = 0;

    ost->muxing_queue_data_threshold = 50*1024*1024;
    MATCH_PER_STREAM_OPT(muxing_queue_data_threshold, i, ost->muxing_queue_data_threshold, oc, st);

    MATCH_PER_STREAM_OPT(bits_per_raw_sample, i, ost->bits_per_raw_sample,
                         oc, st);

    if (oc->oformat->flags & AVFMT_GLOBALHEADER)
        ost->enc_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

    av_dict_copy(&ost->sws_dict, o->g->sws_dict, 0);

    av_dict_copy(&ost->swr_opts, o->g->swr_opts, 0);
    if (ost->enc && av_get_exact_bits_per_sample(ost->enc->id) == 24)
        av_dict_set(&ost->swr_opts, "output_sample_bits", "24", 0);

    ost->source_index = source_index;
    if (source_index >= 0) {
        ost->sync_ist = input_streams[source_index];
        input_streams[source_index]->discard = 0;
        input_streams[source_index]->st->discard = input_streams[source_index]->user_set_discard;
    }
    ost->last_mux_dts = AV_NOPTS_VALUE;

    ost->muxing_queue = av_fifo_alloc2(8, sizeof(AVPacket*), 0);
    if (!ost->muxing_queue)
        exit_program(1);

    MATCH_PER_STREAM_OPT(copy_initial_nonkeyframes, i,
                         ost->copy_initial_nonkeyframes, oc, st);

    return ost;
}

void parse_matrix_coeffs(uint16_t *dest, const char *str)
{
    int i;
    const char *p = str;
    for (i = 0;; i++) {
        dest[i] = atoi(p);
        if (i == 63)
            break;
        p = strchr(p, ',');
        if (!p) {
            av_log(NULL, AV_LOG_FATAL, "Syntax error in matrix \"%s\" at coeff %d\n", str, i);
            exit_program(1);
        }
        p++;
    }
}

/* read file contents into a string */
char *fftools_read_file(const char *filename)
{
    AVIOContext *pb      = NULL;
    int ret = avio_open(&pb, filename, AVIO_FLAG_READ);
    AVBPrint bprint;
    char *str;

    if (ret < 0) {
        av_log(NULL, AV_LOG_ERROR, "Error opening file %s.\n", filename);
        return NULL;
    }

    av_bprint_init(&bprint, 0, AV_BPRINT_SIZE_UNLIMITED);
    ret = avio_read_to_bprint(pb, &bprint, SIZE_MAX);
    avio_closep(&pb);
    if (ret < 0) {
        av_bprint_finalize(&bprint, NULL);
        return NULL;
    }
    ret = av_bprint_finalize(&bprint, &str);
    if (ret < 0)
        return NULL;
    return str;
}

char *get_ost_filters(OptionsContext *o, AVFormatContext *oc,
                             OutputStream *ost)
{
    AVStream *st = ost->st;

    if (ost->filters_script && ost->filters) {
        av_log(NULL, AV_LOG_ERROR, "Both -filter and -filter_script set for "
               "output stream #%d:%d.\n", nb_output_files, st->index);
        exit_program(1);
    }

    if (ost->filters_script)
        return fftools_read_file(ost->filters_script);
    else if (ost->filters)
        return av_strdup(ost->filters);

    return av_strdup(st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO ?
                     "null" : "anull");
}

void check_streamcopy_filters(OptionsContext *o, AVFormatContext *oc,
                                     const OutputStream *ost, enum AVMediaType type)
{
    if (ost->filters_script || ost->filters) {
        av_log(NULL, AV_LOG_ERROR,
               "%s '%s' was defined for %s output stream %d:%d but codec copy was selected.\n"
               "Filtering and streamcopy cannot be used together.\n",
               ost->filters ? "Filtergraph" : "Filtergraph script",
               ost->filters ? ost->filters : ost->filters_script,
               av_get_media_type_string(type), ost->file_index, ost->index);
        exit_program(1);
    }
}

OutputStream *new_video_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *video_enc;
    char *frame_rate = NULL, *max_frame_rate = NULL, *frame_aspect_ratio = NULL;

    ost = new_output_stream(o, oc, AVMEDIA_TYPE_VIDEO, source_index);
    st  = ost->st;
    video_enc = ost->enc_ctx;

    MATCH_PER_STREAM_OPT(frame_rates, str, frame_rate, oc, st);
    if (frame_rate && av_parse_video_rate(&ost->frame_rate, frame_rate) < 0) {
        av_log(NULL, AV_LOG_FATAL, "Invalid framerate value: %s\n", frame_rate);
        exit_program(1);
    }

    MATCH_PER_STREAM_OPT(max_frame_rates, str, max_frame_rate, oc, st);
    if (max_frame_rate && av_parse_video_rate(&ost->max_frame_rate, max_frame_rate) < 0) {
        av_log(NULL, AV_LOG_FATAL, "Invalid maximum framerate value: %s\n", max_frame_rate);
        exit_program(1);
    }

    if (frame_rate && max_frame_rate) {
        av_log(NULL, AV_LOG_ERROR, "Only one of -fpsmax and -r can be set for a stream.\n");
        exit_program(1);
    }

    if ((frame_rate || max_frame_rate) &&
        video_sync_method == VSYNC_PASSTHROUGH)
        av_log(NULL, AV_LOG_ERROR, "Using -vsync passthrough and -r/-fpsmax can produce invalid output files\n");

    MATCH_PER_STREAM_OPT(frame_aspect_ratios, str, frame_aspect_ratio, oc, st);
    if (frame_aspect_ratio) {
        AVRational q;
        if (av_parse_ratio(&q, frame_aspect_ratio, 255, 0, NULL) < 0 ||
            q.num <= 0 || q.den <= 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid aspect ratio: %s\n", frame_aspect_ratio);
            exit_program(1);
        }
        ost->frame_aspect_ratio = q;
    }

    MATCH_PER_STREAM_OPT(filter_scripts, str, ost->filters_script, oc, st);
    MATCH_PER_STREAM_OPT(filters,        str, ost->filters,        oc, st);

    if (!ost->stream_copy) {
        const char *p = NULL;
        char *frame_size = NULL;
        char *frame_pix_fmt = NULL;
        char *intra_matrix = NULL, *inter_matrix = NULL;
        char *chroma_intra_matrix = NULL;
        int do_pass = 0;
        int i;

        MATCH_PER_STREAM_OPT(frame_sizes, str, frame_size, oc, st);
        if (frame_size && av_parse_video_size(&video_enc->width, &video_enc->height, frame_size) < 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid frame size: %s.\n", frame_size);
            exit_program(1);
        }

        MATCH_PER_STREAM_OPT(frame_pix_fmts, str, frame_pix_fmt, oc, st);
        if (frame_pix_fmt && *frame_pix_fmt == '+') {
            ost->keep_pix_fmt = 1;
            if (!*++frame_pix_fmt)
                frame_pix_fmt = NULL;
        }
        if (frame_pix_fmt && (video_enc->pix_fmt = av_get_pix_fmt(frame_pix_fmt)) == AV_PIX_FMT_NONE) {
            av_log(NULL, AV_LOG_FATAL, "Unknown pixel format requested: %s.\n", frame_pix_fmt);
            exit_program(1);
        }
        st->sample_aspect_ratio = video_enc->sample_aspect_ratio;

        MATCH_PER_STREAM_OPT(intra_matrices, str, intra_matrix, oc, st);
        if (intra_matrix) {
            if (!(video_enc->intra_matrix = av_mallocz(sizeof(*video_enc->intra_matrix) * 64))) {
                av_log(NULL, AV_LOG_FATAL, "Could not allocate memory for intra matrix.\n");
                exit_program(1);
            }
            parse_matrix_coeffs(video_enc->intra_matrix, intra_matrix);
        }
        MATCH_PER_STREAM_OPT(chroma_intra_matrices, str, chroma_intra_matrix, oc, st);
        if (chroma_intra_matrix) {
            uint16_t *p = av_mallocz(sizeof(*video_enc->chroma_intra_matrix) * 64);
            if (!p) {
                av_log(NULL, AV_LOG_FATAL, "Could not allocate memory for intra matrix.\n");
                exit_program(1);
            }
            video_enc->chroma_intra_matrix = p;
            parse_matrix_coeffs(p, chroma_intra_matrix);
        }
        MATCH_PER_STREAM_OPT(inter_matrices, str, inter_matrix, oc, st);
        if (inter_matrix) {
            if (!(video_enc->inter_matrix = av_mallocz(sizeof(*video_enc->inter_matrix) * 64))) {
                av_log(NULL, AV_LOG_FATAL, "Could not allocate memory for inter matrix.\n");
                exit_program(1);
            }
            parse_matrix_coeffs(video_enc->inter_matrix, inter_matrix);
        }

        MATCH_PER_STREAM_OPT(rc_overrides, str, p, oc, st);
        for (i = 0; p; i++) {
            int start, end, q;
            int e = sscanf(p, "%d,%d,%d", &start, &end, &q);
            if (e != 3) {
                av_log(NULL, AV_LOG_FATAL, "error parsing rc_override\n");
                exit_program(1);
            }
            video_enc->rc_override =
                av_realloc_array(video_enc->rc_override,
                                 i + 1, sizeof(RcOverride));
            if (!video_enc->rc_override) {
                av_log(NULL, AV_LOG_FATAL, "Could not (re)allocate memory for rc_override.\n");
                exit_program(1);
            }
            video_enc->rc_override[i].start_frame = start;
            video_enc->rc_override[i].end_frame   = end;
            if (q > 0) {
                video_enc->rc_override[i].qscale         = q;
                video_enc->rc_override[i].quality_factor = 1.0;
            }
            else {
                video_enc->rc_override[i].qscale         = 0;
                video_enc->rc_override[i].quality_factor = -q/100.0;
            }
            p = strchr(p, '/');
            if (p) p++;
        }
        video_enc->rc_override_count = i;

        if (do_psnr)
            video_enc->flags|= AV_CODEC_FLAG_PSNR;

        /* two pass mode */
        MATCH_PER_STREAM_OPT(pass, i, do_pass, oc, st);
        if (do_pass) {
            if (do_pass & 1) {
                video_enc->flags |= AV_CODEC_FLAG_PASS1;
                av_dict_set(&ost->encoder_opts, "flags", "+pass1", AV_DICT_APPEND);
            }
            if (do_pass & 2) {
                video_enc->flags |= AV_CODEC_FLAG_PASS2;
                av_dict_set(&ost->encoder_opts, "flags", "+pass2", AV_DICT_APPEND);
            }
        }

        MATCH_PER_STREAM_OPT(passlogfiles, str, ost->logfile_prefix, oc, st);
        if (ost->logfile_prefix &&
            !(ost->logfile_prefix = av_strdup(ost->logfile_prefix)))
            exit_program(1);

        if (do_pass) {
            char logfilename[1024];
            FILE *f;

            snprintf(logfilename, sizeof(logfilename), "%s-%d.log",
                     ost->logfile_prefix ? ost->logfile_prefix :
                                           DEFAULT_PASS_LOGFILENAME_PREFIX,
                     nb_output_streams - 1);
            if (!strcmp(ost->enc->name, "libx264")) {
                av_dict_set(&ost->encoder_opts, "stats", logfilename, AV_DICT_DONT_OVERWRITE);
            } else {
                if (video_enc->flags & AV_CODEC_FLAG_PASS2) {
                    char  *logbuffer = fftools_read_file(logfilename);

                    if (!logbuffer) {
                        av_log(NULL, AV_LOG_FATAL, "Error reading log file '%s' for pass-2 encoding\n",
                               logfilename);
                        exit_program(1);
                    }
                    video_enc->stats_in = logbuffer;
                }
                if (video_enc->flags & AV_CODEC_FLAG_PASS1) {
                    f = fopen_utf8(logfilename, "wb");
                    if (!f) {
                        av_log(NULL, AV_LOG_FATAL,
                               "Cannot write log file '%s' for pass-1 encoding: %s\n",
                               logfilename, strerror(errno));
                        exit_program(1);
                    }
                    ost->logfile = f;
                }
            }
        }

        MATCH_PER_STREAM_OPT(forced_key_frames, str, ost->forced_keyframes, oc, st);
        if (ost->forced_keyframes)
            ost->forced_keyframes = av_strdup(ost->forced_keyframes);

        MATCH_PER_STREAM_OPT(force_fps, i, ost->force_fps, oc, st);

        ost->top_field_first = -1;
        MATCH_PER_STREAM_OPT(top_field_first, i, ost->top_field_first, oc, st);

        ost->vsync_method = video_sync_method;
        MATCH_PER_STREAM_OPT(fps_mode, str, ost->fps_mode, oc, st);
        if (ost->fps_mode)
            parse_and_set_vsync(ost->fps_mode, &ost->vsync_method, ost->file_index, ost->index, 0);

        if (ost->vsync_method == VSYNC_AUTO) {
            if (!strcmp(oc->oformat->name, "avi")) {
                ost->vsync_method = VSYNC_VFR;
            } else {
                ost->vsync_method = (oc->oformat->flags & AVFMT_VARIABLE_FPS)       ?
                                     ((oc->oformat->flags & AVFMT_NOTIMESTAMPS) ?
                                      VSYNC_PASSTHROUGH : VSYNC_VFR)                :
                                     VSYNC_CFR;
            }

            if (ost->source_index >= 0 && ost->vsync_method == VSYNC_CFR) {
                const InputStream *ist = input_streams[ost->source_index];
                const InputFile *ifile = input_files[ist->file_index];

                if (ifile->nb_streams == 1 && ifile->input_ts_offset == 0)
                    ost->vsync_method = VSYNC_VSCFR;
            }

            if (ost->vsync_method == VSYNC_CFR && copy_ts) {
                ost->vsync_method = VSYNC_VSCFR;
            }
        }
        ost->is_cfr = (ost->vsync_method == VSYNC_CFR || ost->vsync_method == VSYNC_VSCFR);

        ost->avfilter = get_ost_filters(o, oc, ost);
        if (!ost->avfilter)
            exit_program(1);

        ost->last_frame = av_frame_alloc();
        if (!ost->last_frame)
            exit_program(1);
    }

    if (ost->stream_copy)
        check_streamcopy_filters(o, oc, ost, AVMEDIA_TYPE_VIDEO);

    return ost;
}

OutputStream *new_audio_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    int n;
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *audio_enc;

    ost = new_output_stream(o, oc, AVMEDIA_TYPE_AUDIO, source_index);
    st  = ost->st;

    audio_enc = ost->enc_ctx;
    audio_enc->codec_type = AVMEDIA_TYPE_AUDIO;

    MATCH_PER_STREAM_OPT(filter_scripts, str, ost->filters_script, oc, st);
    MATCH_PER_STREAM_OPT(filters,        str, ost->filters,        oc, st);

    if (!ost->stream_copy) {
        int channels = 0;
        char *layout = NULL;
        char *sample_fmt = NULL;

        MATCH_PER_STREAM_OPT(audio_channels, i, channels, oc, st);
        if (channels) {
            audio_enc->ch_layout.order       = AV_CHANNEL_ORDER_UNSPEC;
            audio_enc->ch_layout.nb_channels = channels;
        }

        MATCH_PER_STREAM_OPT(audio_ch_layouts, str, layout, oc, st);
        if (layout) {
            if (av_channel_layout_from_string(&audio_enc->ch_layout, layout) < 0) {
#if FF_API_OLD_CHANNEL_LAYOUT
                uint64_t mask;
                AV_NOWARN_DEPRECATED({
                mask = av_get_channel_layout(layout);
                })
                if (!mask) {
#endif
                    av_log(NULL, AV_LOG_FATAL, "Unknown channel layout: %s\n", layout);
                    exit_program(1);
#if FF_API_OLD_CHANNEL_LAYOUT
                }
                av_log(NULL, AV_LOG_WARNING, "Channel layout '%s' uses a deprecated syntax.\n",
                       layout);
                av_channel_layout_from_mask(&audio_enc->ch_layout, mask);
#endif
            }
        }

        MATCH_PER_STREAM_OPT(sample_fmts, str, sample_fmt, oc, st);
        if (sample_fmt &&
            (audio_enc->sample_fmt = av_get_sample_fmt(sample_fmt)) == AV_SAMPLE_FMT_NONE) {
            av_log(NULL, AV_LOG_FATAL, "Invalid sample format '%s'\n", sample_fmt);
            exit_program(1);
        }

        MATCH_PER_STREAM_OPT(audio_sample_rate, i, audio_enc->sample_rate, oc, st);

        MATCH_PER_STREAM_OPT(apad, str, ost->apad, oc, st);
        ost->apad = av_strdup(ost->apad);

        ost->avfilter = get_ost_filters(o, oc, ost);
        if (!ost->avfilter)
            exit_program(1);

        /* check for channel mapping for this audio stream */
        for (n = 0; n < o->nb_audio_channel_maps; n++) {
            AudioChannelMap *map = &o->audio_channel_maps[n];
            if ((map->ofile_idx   == -1 || ost->file_index == map->ofile_idx) &&
                (map->ostream_idx == -1 || ost->st->index  == map->ostream_idx)) {
                InputStream *ist;

                if (map->channel_idx == -1) {
                    ist = NULL;
                } else if (ost->source_index < 0) {
                    av_log(NULL, AV_LOG_FATAL, "Cannot determine input stream for channel mapping %d.%d\n",
                           ost->file_index, ost->st->index);
                    continue;
                } else {
                    ist = input_streams[ost->source_index];
                }

                if (!ist || (ist->file_index == map->file_idx && ist->st->index == map->stream_idx)) {
                    if (av_reallocp_array(&ost->audio_channels_map,
                                          ost->audio_channels_mapped + 1,
                                          sizeof(*ost->audio_channels_map)
                                          ) < 0 )
                        exit_program(1);

                    ost->audio_channels_map[ost->audio_channels_mapped++] = map->channel_idx;
                }
            }
        }
    }

    if (ost->stream_copy)
        check_streamcopy_filters(o, oc, ost, AVMEDIA_TYPE_AUDIO);

    return ost;
}

OutputStream *new_data_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    OutputStream *ost;

    ost = new_output_stream(o, oc, AVMEDIA_TYPE_DATA, source_index);
    if (!ost->stream_copy) {
        av_log(NULL, AV_LOG_FATAL, "Data stream encoding not supported yet (only streamcopy)\n");
        exit_program(1);
    }

    return ost;
}

OutputStream *new_unknown_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    OutputStream *ost;

    ost = new_output_stream(o, oc, AVMEDIA_TYPE_UNKNOWN, source_index);
    if (!ost->stream_copy) {
        av_log(NULL, AV_LOG_FATAL, "Unknown stream encoding not supported yet (only streamcopy)\n");
        exit_program(1);
    }

    return ost;
}

OutputStream *new_attachment_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    OutputStream *ost = new_output_stream(o, oc, AVMEDIA_TYPE_ATTACHMENT, source_index);
    ost->stream_copy = 1;
    ost->finished    = 1;
    return ost;
}

OutputStream *new_subtitle_stream(OptionsContext *o, AVFormatContext *oc, int source_index)
{
    AVStream *st;
    OutputStream *ost;
    AVCodecContext *subtitle_enc;

    ost = new_output_stream(o, oc, AVMEDIA_TYPE_SUBTITLE, source_index);
    st  = ost->st;
    subtitle_enc = ost->enc_ctx;

    subtitle_enc->codec_type = AVMEDIA_TYPE_SUBTITLE;

    if (!ost->stream_copy) {
        char *frame_size = NULL;

        MATCH_PER_STREAM_OPT(frame_sizes, str, frame_size, oc, st);
        if (frame_size && av_parse_video_size(&subtitle_enc->width, &subtitle_enc->height, frame_size) < 0) {
            av_log(NULL, AV_LOG_FATAL, "Invalid frame size: %s.\n", frame_size);
            exit_program(1);
        }
    }

    return ost;
}

/* arg format is "output-stream-index:streamid-value". */
int opt_streamid(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    int idx;
    char *p;
    char idx_str[16];

    av_strlcpy(idx_str, arg, sizeof(idx_str));
    p = strchr(idx_str, ':');
    if (!p) {
        av_log(NULL, AV_LOG_FATAL,
               "Invalid value '%s' for option '%s', required syntax is 'index:value'\n",
               arg, opt);
        exit_program(1);
    }
    *p++ = '\0';
    idx = parse_number_or_die(opt, idx_str, OPT_INT, 0, MAX_STREAMS-1);
    o->streamid_map = grow_array(o->streamid_map, sizeof(*o->streamid_map), &o->nb_streamid_map, idx+1);
    o->streamid_map[idx] = parse_number_or_die(opt, p, OPT_INT, 0, INT_MAX);
    return 0;
}

int copy_chapters(InputFile *ifile, OutputFile *ofile, AVFormatContext *os,
                         int copy_metadata)
{
    AVFormatContext *is = ifile->ctx;
    AVChapter **tmp;
    int i;

    tmp = av_realloc_f(os->chapters, is->nb_chapters + os->nb_chapters, sizeof(*os->chapters));
    if (!tmp)
        return AVERROR(ENOMEM);
    os->chapters = tmp;

    for (i = 0; i < is->nb_chapters; i++) {
        AVChapter *in_ch = is->chapters[i], *out_ch;
        int64_t start_time = (ofile->start_time == AV_NOPTS_VALUE) ? 0 : ofile->start_time;
        int64_t ts_off   = av_rescale_q(start_time - ifile->ts_offset,
                                       AV_TIME_BASE_Q, in_ch->time_base);
        int64_t rt       = (ofile->recording_time == INT64_MAX) ? INT64_MAX :
                           av_rescale_q(ofile->recording_time, AV_TIME_BASE_Q, in_ch->time_base);


        if (in_ch->end < ts_off)
            continue;
        if (rt != INT64_MAX && in_ch->start > rt + ts_off)
            break;

        out_ch = av_mallocz(sizeof(AVChapter));
        if (!out_ch)
            return AVERROR(ENOMEM);

        out_ch->id        = in_ch->id;
        out_ch->time_base = in_ch->time_base;
        out_ch->start     = FFMAX(0,  in_ch->start - ts_off);
        out_ch->end       = FFMIN(rt, in_ch->end   - ts_off);

        if (copy_metadata)
            av_dict_copy(&out_ch->metadata, in_ch->metadata, 0);

        os->chapters[os->nb_chapters++] = out_ch;
    }
    return 0;
}

int set_dispositions(OutputFile *of, AVFormatContext *ctx)
{
    int nb_streams[AVMEDIA_TYPE_NB]   = { 0 };
    int have_default[AVMEDIA_TYPE_NB] = { 0 };
    int have_manual = 0;

    // first, copy the input dispositions
    for (int i = 0; i < ctx->nb_streams; i++) {
        OutputStream *ost = output_streams[of->ost_index + i];

        nb_streams[ost->st->codecpar->codec_type]++;

        have_manual |= !!ost->disposition;

        if (ost->source_index >= 0) {
            ost->st->disposition = input_streams[ost->source_index]->st->disposition;

            if (ost->st->disposition & AV_DISPOSITION_DEFAULT)
                have_default[ost->st->codecpar->codec_type] = 1;
        }
    }

    if (have_manual) {
        // process manually set dispositions - they override the above copy
        for (int i = 0; i < ctx->nb_streams; i++) {
            OutputStream *ost = output_streams[of->ost_index + i];
            int ret;

            if (!ost->disposition)
                continue;

#if LIBAVFORMAT_VERSION_MAJOR >= 60
            ret = av_opt_set(ost->st, "disposition", ost->disposition, 0);
#else
            {
                const AVClass *class = av_stream_get_class();
                const AVOption    *o = av_opt_find(&class, "disposition", NULL, 0, AV_OPT_SEARCH_FAKE_OBJ);

                av_assert0(o);
                ret = av_opt_eval_flags(&class, o, ost->disposition, &ost->st->disposition);
            }
#endif

            if (ret < 0)
                return ret;
        }
    } else {
        // For each media type with more than one stream, find a suitable stream to
        // mark as default, unless one is already marked default.
        // "Suitable" means the first of that type, skipping attached pictures.
        for (int i = 0; i < ctx->nb_streams; i++) {
            OutputStream *ost = output_streams[of->ost_index + i];
            enum AVMediaType type = ost->st->codecpar->codec_type;

            if (nb_streams[type] < 2 || have_default[type] ||
                ost->st->disposition & AV_DISPOSITION_ATTACHED_PIC)
                continue;

            ost->st->disposition |= AV_DISPOSITION_DEFAULT;
            have_default[type] = 1;
        }
    }

    return 0;
}

void init_output_filter(OutputFilter *ofilter, OptionsContext *o,
                               AVFormatContext *oc)
{
    OutputStream *ost;

    switch (ofilter->type) {
    case AVMEDIA_TYPE_VIDEO: ost = new_video_stream(o, oc, -1); break;
    case AVMEDIA_TYPE_AUDIO: ost = new_audio_stream(o, oc, -1); break;
    default:
        av_log(NULL, AV_LOG_FATAL, "Only video and audio filters are supported "
               "currently.\n");
        exit_program(1);
    }

    ost->filter       = ofilter;

    ofilter->ost      = ost;
    ofilter->format   = -1;

    if (ost->stream_copy) {
        av_log(NULL, AV_LOG_ERROR, "Streamcopy requested for output stream %d:%d, "
               "which is fed from a complex filtergraph. Filtering and streamcopy "
               "cannot be used together.\n", ost->file_index, ost->index);
        exit_program(1);
    }

    if (ost->avfilter && (ost->filters || ost->filters_script)) {
        const char *opt = ost->filters ? "-vf/-af/-filter" : "-filter_script";
        av_log(NULL, AV_LOG_ERROR,
               "%s '%s' was specified through the %s option "
               "for output stream %d:%d, which is fed from a complex filtergraph.\n"
               "%s and -filter_complex cannot be used together for the same stream.\n",
               ost->filters ? "Filtergraph" : "Filtergraph script",
               ost->filters ? ost->filters : ost->filters_script,
               opt, ost->file_index, ost->index, opt);
        exit_program(1);
    }

    avfilter_inout_free(&ofilter->out_tmp);
}

int init_complex_filters(void)
{
    int i, ret = 0;

    for (i = 0; i < nb_filtergraphs; i++) {
        ret = init_complex_filtergraph(filtergraphs[i]);
        if (ret < 0)
            return ret;
    }
    return 0;
}

void set_channel_layout(OutputFilter *f, OutputStream *ost)
{
    int i, err;

    if (ost->enc_ctx->ch_layout.order != AV_CHANNEL_ORDER_UNSPEC) {
        /* Pass the layout through for all orders but UNSPEC */
        err = av_channel_layout_copy(&f->ch_layout, &ost->enc_ctx->ch_layout);
        if (err < 0)
            exit_program(1);
        return;
    }

    /* Requested layout is of order UNSPEC */
    if (!ost->enc->ch_layouts) {
        /* Use the default native layout for the requested amount of channels when the
           encoder doesn't have a list of supported layouts */
        av_channel_layout_default(&f->ch_layout, ost->enc_ctx->ch_layout.nb_channels);
        return;
    }
    /* Encoder has a list of supported layouts. Pick the first layout in it with the
       same amount of channels as the requested layout */
    for (i = 0; ost->enc->ch_layouts[i].nb_channels; i++) {
        if (ost->enc->ch_layouts[i].nb_channels == ost->enc_ctx->ch_layout.nb_channels)
            break;
    }
    if (ost->enc->ch_layouts[i].nb_channels) {
        /* Use it if one is found */
        err = av_channel_layout_copy(&f->ch_layout, &ost->enc->ch_layouts[i]);
        if (err < 0)
            exit_program(1);
        return;
    }
    /* If no layout for the amount of channels requested was found, use the default
       native layout for it. */
    av_channel_layout_default(&f->ch_layout, ost->enc_ctx->ch_layout.nb_channels);
}

int open_output_file(OptionsContext *o, const char *filename)
{
    AVFormatContext *oc;
    int i, j, err;
    OutputFile *of;
    OutputStream *ost;
    InputStream  *ist;
    AVDictionary *unused_opts = NULL;
    const AVDictionaryEntry *e = NULL;

    if (o->stop_time != INT64_MAX && o->recording_time != INT64_MAX) {
        o->stop_time = INT64_MAX;
        av_log(NULL, AV_LOG_WARNING, "-t and -to cannot be used together; using -t.\n");
    }

    if (o->stop_time != INT64_MAX && o->recording_time == INT64_MAX) {
        int64_t start_time = o->start_time == AV_NOPTS_VALUE ? 0 : o->start_time;
        if (o->stop_time <= start_time) {
            av_log(NULL, AV_LOG_ERROR, "-to value smaller than -ss; aborting.\n");
            exit_program(1);
        } else {
            o->recording_time = o->stop_time - start_time;
        }
    }

    of = ALLOC_ARRAY_ELEM(output_files, nb_output_files);

    of->index          = nb_output_files - 1;
    of->ost_index      = nb_output_streams;
    of->recording_time = o->recording_time;
    of->start_time     = o->start_time;
    of->limit_filesize = o->limit_filesize;
    of->shortest       = o->shortest;
    av_dict_copy(&of->opts, o->g->format_opts, 0);

    if (!strcmp(filename, "-"))
        filename = "pipe:";

    err = avformat_alloc_output_context2(&oc, NULL, o->format, filename);
    if (!oc) {
        print_error(filename, err);
        exit_program(1);
    }

    of->ctx = oc;
    of->format = oc->oformat;
    if (o->recording_time != INT64_MAX)
        oc->duration = o->recording_time;

    oc->interrupt_callback = int_cb;

    if (o->bitexact) {
        oc->flags    |= AVFMT_FLAG_BITEXACT;
    }

    /* create streams for all unlabeled output pads */
    for (i = 0; i < nb_filtergraphs; i++) {
        FilterGraph *fg = filtergraphs[i];
        for (j = 0; j < fg->nb_outputs; j++) {
            OutputFilter *ofilter = fg->outputs[j];

            if (!ofilter->out_tmp || ofilter->out_tmp->name)
                continue;

            switch (ofilter->type) {
            case AVMEDIA_TYPE_VIDEO:    o->video_disable    = 1; break;
            case AVMEDIA_TYPE_AUDIO:    o->audio_disable    = 1; break;
            case AVMEDIA_TYPE_SUBTITLE: o->subtitle_disable = 1; break;
            }
            init_output_filter(ofilter, o, oc);
        }
    }

    if (!o->nb_stream_maps) {
        char *subtitle_codec_name = NULL;
        /* pick the "best" stream of each type */

        /* video: highest resolution */
        if (!o->video_disable && av_guess_codec(oc->oformat, NULL, filename, NULL, AVMEDIA_TYPE_VIDEO) != AV_CODEC_ID_NONE) {
            int best_score = 0, idx = -1;
            int qcr = avformat_query_codec(oc->oformat, oc->oformat->video_codec, 0);
            for (j = 0; j < nb_input_files; j++) {
                InputFile *ifile = input_files[j];
                int file_best_score = 0, file_best_idx = -1;
                for (i = 0; i < ifile->nb_streams; i++) {
                    int score;
                    ist = input_streams[ifile->ist_index + i];
                    score = ist->st->codecpar->width * ist->st->codecpar->height
                               + 100000000 * !!(ist->st->event_flags & AVSTREAM_EVENT_FLAG_NEW_PACKETS)
                               + 5000000*!!(ist->st->disposition & AV_DISPOSITION_DEFAULT);
                    if (ist->user_set_discard == AVDISCARD_ALL)
                        continue;
                    if((qcr!=MKTAG('A', 'P', 'I', 'C')) && (ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC))
                        score = 1;
                    if (ist->st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
                        score > file_best_score) {
                        if((qcr==MKTAG('A', 'P', 'I', 'C')) && !(ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC))
                            continue;
                        file_best_score = score;
                        file_best_idx = ifile->ist_index + i;
                    }
                }
                if (file_best_idx >= 0) {
                    if((qcr == MKTAG('A', 'P', 'I', 'C')) || !(ist->st->disposition & AV_DISPOSITION_ATTACHED_PIC))
                        file_best_score -= 5000000*!!(input_streams[file_best_idx]->st->disposition & AV_DISPOSITION_DEFAULT);
                    if (file_best_score > best_score) {
                        best_score = file_best_score;
                        idx = file_best_idx;
                    }
               }
            }
            if (idx >= 0)
                new_video_stream(o, oc, idx);
        }

        /* audio: most channels */
        if (!o->audio_disable && av_guess_codec(oc->oformat, NULL, filename, NULL, AVMEDIA_TYPE_AUDIO) != AV_CODEC_ID_NONE) {
            int best_score = 0, idx = -1;
            for (j = 0; j < nb_input_files; j++) {
                InputFile *ifile = input_files[j];
                int file_best_score = 0, file_best_idx = -1;
                for (i = 0; i < ifile->nb_streams; i++) {
                    int score;
                    ist = input_streams[ifile->ist_index + i];
                    score = ist->st->codecpar->ch_layout.nb_channels
                            + 100000000 * !!(ist->st->event_flags & AVSTREAM_EVENT_FLAG_NEW_PACKETS)
                            + 5000000*!!(ist->st->disposition & AV_DISPOSITION_DEFAULT);
                    if (ist->user_set_discard == AVDISCARD_ALL)
                        continue;
                    if (ist->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO &&
                        score > file_best_score) {
                        file_best_score = score;
                        file_best_idx = ifile->ist_index + i;
                    }
                }
                if (file_best_idx >= 0) {
                    file_best_score -= 5000000*!!(input_streams[file_best_idx]->st->disposition & AV_DISPOSITION_DEFAULT);
                    if (file_best_score > best_score) {
                        best_score = file_best_score;
                        idx = file_best_idx;
                    }
               }
            }
            if (idx >= 0)
                new_audio_stream(o, oc, idx);
        }

        /* subtitles: pick first */
        MATCH_PER_TYPE_OPT(codec_names, str, subtitle_codec_name, oc, "s");
        if (!o->subtitle_disable && (avcodec_find_encoder(oc->oformat->subtitle_codec) || subtitle_codec_name)) {
            for (i = 0; i < nb_input_streams; i++)
                if (input_streams[i]->st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) {
                    AVCodecDescriptor const *input_descriptor =
                        avcodec_descriptor_get(input_streams[i]->st->codecpar->codec_id);
                    AVCodecDescriptor const *output_descriptor = NULL;
                    AVCodec const *output_codec =
                        avcodec_find_encoder(oc->oformat->subtitle_codec);
                    int input_props = 0, output_props = 0;
                    if (input_streams[i]->user_set_discard == AVDISCARD_ALL)
                        continue;
                    if (output_codec)
                        output_descriptor = avcodec_descriptor_get(output_codec->id);
                    if (input_descriptor)
                        input_props = input_descriptor->props & (AV_CODEC_PROP_TEXT_SUB | AV_CODEC_PROP_BITMAP_SUB);
                    if (output_descriptor)
                        output_props = output_descriptor->props & (AV_CODEC_PROP_TEXT_SUB | AV_CODEC_PROP_BITMAP_SUB);
                    if (subtitle_codec_name ||
                        input_props & output_props ||
                        // Map dvb teletext which has neither property to any output subtitle encoder
                        (input_descriptor && output_descriptor &&
                        (!input_descriptor->props ||
                         !output_descriptor->props))) {
                        new_subtitle_stream(o, oc, i);
                        break;
                    }
                }
        }
        /* Data only if codec id match */
        if (!o->data_disable ) {
            enum AVCodecID codec_id = av_guess_codec(oc->oformat, NULL, filename, NULL, AVMEDIA_TYPE_DATA);
            for (i = 0; codec_id != AV_CODEC_ID_NONE && i < nb_input_streams; i++) {
                if (input_streams[i]->user_set_discard == AVDISCARD_ALL)
                    continue;
                if (input_streams[i]->st->codecpar->codec_type == AVMEDIA_TYPE_DATA
                    && input_streams[i]->st->codecpar->codec_id == codec_id )
                    new_data_stream(o, oc, i);
            }
        }
    } else {
        for (i = 0; i < o->nb_stream_maps; i++) {
            StreamMap *map = &o->stream_maps[i];

            if (map->disabled)
                continue;

            if (map->linklabel) {
                FilterGraph *fg;
                OutputFilter *ofilter = NULL;
                int j, k;

                for (j = 0; j < nb_filtergraphs; j++) {
                    fg = filtergraphs[j];
                    for (k = 0; k < fg->nb_outputs; k++) {
                        AVFilterInOut *out = fg->outputs[k]->out_tmp;
                        if (out && !strcmp(out->name, map->linklabel)) {
                            ofilter = fg->outputs[k];
                            goto loop_end;
                        }
                    }
                }
loop_end:
                if (!ofilter) {
                    av_log(NULL, AV_LOG_FATAL, "Output with label '%s' does not exist "
                           "in any defined filter graph, or was already used elsewhere.\n", map->linklabel);
                    exit_program(1);
                }
                init_output_filter(ofilter, o, oc);
            } else {
                int src_idx = input_files[map->file_index]->ist_index + map->stream_index;

                ist = input_streams[input_files[map->file_index]->ist_index + map->stream_index];
                if (ist->user_set_discard == AVDISCARD_ALL) {
                    av_log(NULL, AV_LOG_FATAL, "Stream #%d:%d is disabled and cannot be mapped.\n",
                           map->file_index, map->stream_index);
                    exit_program(1);
                }
                if(o->subtitle_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)
                    continue;
                if(o->   audio_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
                    continue;
                if(o->   video_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
                    continue;
                if(o->    data_disable && ist->st->codecpar->codec_type == AVMEDIA_TYPE_DATA)
                    continue;

                ost = NULL;
                switch (ist->st->codecpar->codec_type) {
                case AVMEDIA_TYPE_VIDEO:      ost = new_video_stream     (o, oc, src_idx); break;
                case AVMEDIA_TYPE_AUDIO:      ost = new_audio_stream     (o, oc, src_idx); break;
                case AVMEDIA_TYPE_SUBTITLE:   ost = new_subtitle_stream  (o, oc, src_idx); break;
                case AVMEDIA_TYPE_DATA:       ost = new_data_stream      (o, oc, src_idx); break;
                case AVMEDIA_TYPE_ATTACHMENT: ost = new_attachment_stream(o, oc, src_idx); break;
                case AVMEDIA_TYPE_UNKNOWN:
                    if (copy_unknown_streams) {
                        ost = new_unknown_stream   (o, oc, src_idx);
                        break;
                    }
                default:
                    av_log(NULL, ignore_unknown_streams ? AV_LOG_WARNING : AV_LOG_FATAL,
                           "Cannot map stream #%d:%d - unsupported type.\n",
                           map->file_index, map->stream_index);
                    if (!ignore_unknown_streams) {
                        av_log(NULL, AV_LOG_FATAL,
                               "If you want unsupported types ignored instead "
                               "of failing, please use the -ignore_unknown option\n"
                               "If you want them copied, please use -copy_unknown\n");
                        exit_program(1);
                    }
                }
                if (ost)
                    ost->sync_ist = input_streams[  input_files[map->sync_file_index]->ist_index
                                                  + map->sync_stream_index];
            }
        }
    }

    /* handle attached files */
    for (i = 0; i < o->nb_attachments; i++) {
        AVIOContext *pb;
        uint8_t *attachment;
        const char *p;
        int64_t len;

        if ((err = avio_open2(&pb, o->attachments[i], AVIO_FLAG_READ, &int_cb, NULL)) < 0) {
            av_log(NULL, AV_LOG_FATAL, "Could not open attachment file %s.\n",
                   o->attachments[i]);
            exit_program(1);
        }
        if ((len = avio_size(pb)) <= 0) {
            av_log(NULL, AV_LOG_FATAL, "Could not get size of the attachment %s.\n",
                   o->attachments[i]);
            exit_program(1);
        }
        if (len > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE ||
            !(attachment = av_malloc(len + AV_INPUT_BUFFER_PADDING_SIZE))) {
            av_log(NULL, AV_LOG_FATAL, "Attachment %s too large.\n",
                   o->attachments[i]);
            exit_program(1);
        }
        avio_read(pb, attachment, len);
        memset(attachment + len, 0, AV_INPUT_BUFFER_PADDING_SIZE);

        ost = new_attachment_stream(o, oc, -1);
        ost->stream_copy               = 0;
        ost->attachment_filename       = o->attachments[i];
        ost->st->codecpar->extradata      = attachment;
        ost->st->codecpar->extradata_size = len;

        p = strrchr(o->attachments[i], '/');
        av_dict_set(&ost->st->metadata, "filename", (p && *p) ? p + 1 : o->attachments[i], AV_DICT_DONT_OVERWRITE);
        avio_closep(&pb);
    }

    if (!oc->nb_streams && !(oc->oformat->flags & AVFMT_NOSTREAMS)) {
        av_dump_format(oc, nb_output_files - 1, oc->url, 1);
        av_log(NULL, AV_LOG_ERROR, "Output file #%d does not contain any stream\n", nb_output_files - 1);
        exit_program(1);
    }

    /* check if all codec options have been used */
    unused_opts = strip_specifiers(o->g->codec_opts);
    for (i = of->ost_index; i < nb_output_streams; i++) {
        e = NULL;
        while ((e = av_dict_get(output_streams[i]->encoder_opts, "", e,
                                AV_DICT_IGNORE_SUFFIX)))
            av_dict_set(&unused_opts, e->key, NULL, 0);
    }

    e = NULL;
    while ((e = av_dict_get(unused_opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
        const AVClass *class = avcodec_get_class();
        const AVOption *option = av_opt_find(&class, e->key, NULL, 0,
                                             AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
        const AVClass *fclass = avformat_get_class();
        const AVOption *foption = av_opt_find(&fclass, e->key, NULL, 0,
                                              AV_OPT_SEARCH_CHILDREN | AV_OPT_SEARCH_FAKE_OBJ);
        if (!option || foption)
            continue;


        if (!(option->flags & AV_OPT_FLAG_ENCODING_PARAM)) {
            av_log(NULL, AV_LOG_ERROR, "Codec AVOption %s (%s) specified for "
                   "output file #%d (%s) is not an encoding option.\n", e->key,
                   option->help ? option->help : "", nb_output_files - 1,
                   filename);
            exit_program(1);
        }

        // gop_timecode is injected by generic code but not always used
        if (!strcmp(e->key, "gop_timecode"))
            continue;

        av_log(NULL, AV_LOG_WARNING, "Codec AVOption %s (%s) specified for "
               "output file #%d (%s) has not been used for any stream. The most "
               "likely reason is either wrong type (e.g. a video option with "
               "no video streams) or that it is a private option of some encoder "
               "which was not actually used for any stream.\n", e->key,
               option->help ? option->help : "", nb_output_files - 1, filename);
    }
    av_dict_free(&unused_opts);

    /* set the decoding_needed flags and create simple filtergraphs */
    for (i = of->ost_index; i < nb_output_streams; i++) {
        OutputStream *ost = output_streams[i];

        if (ost->encoding_needed && ost->source_index >= 0) {
            InputStream *ist = input_streams[ost->source_index];
            ist->decoding_needed |= DECODING_FOR_OST;
            ist->processing_needed = 1;

            if (ost->st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO ||
                ost->st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
                err = init_simple_filtergraph(ist, ost);
                if (err < 0) {
                    av_log(NULL, AV_LOG_ERROR,
                           "Error initializing a simple filtergraph between streams "
                           "%d:%d->%d:%d\n", ist->file_index, ost->source_index,
                           nb_output_files - 1, ost->st->index);
                    exit_program(1);
                }
            }
        } else if (ost->stream_copy && ost->source_index >= 0) {
            InputStream *ist = input_streams[ost->source_index];
            ist->processing_needed = 1;
        }

        /* set the filter output constraints */
        if (ost->filter) {
            OutputFilter *f = ost->filter;
            switch (ost->enc_ctx->codec_type) {
            case AVMEDIA_TYPE_VIDEO:
                f->frame_rate = ost->frame_rate;
                f->width      = ost->enc_ctx->width;
                f->height     = ost->enc_ctx->height;
                if (ost->enc_ctx->pix_fmt != AV_PIX_FMT_NONE) {
                    f->format = ost->enc_ctx->pix_fmt;
                } else {
                    f->formats = ost->enc->pix_fmts;
                }
                break;
            case AVMEDIA_TYPE_AUDIO:
                if (ost->enc_ctx->sample_fmt != AV_SAMPLE_FMT_NONE) {
                    f->format = ost->enc_ctx->sample_fmt;
                } else {
                    f->formats = ost->enc->sample_fmts;
                }
                if (ost->enc_ctx->sample_rate) {
                    f->sample_rate = ost->enc_ctx->sample_rate;
                } else {
                    f->sample_rates = ost->enc->supported_samplerates;
                }
                if (ost->enc_ctx->ch_layout.nb_channels) {
                    set_channel_layout(f, ost);
                } else if (ost->enc->ch_layouts) {
                    f->ch_layouts = ost->enc->ch_layouts;
                }
                break;
            }
        }
    }

    /* check filename in case of an image number is expected */
    if (oc->oformat->flags & AVFMT_NEEDNUMBER) {
        if (!av_filename_number_test(oc->url)) {
            print_error(oc->url, AVERROR(EINVAL));
            exit_program(1);
        }
    }

    if (!(oc->oformat->flags & AVFMT_NOSTREAMS) && !input_stream_potentially_available) {
        av_log(NULL, AV_LOG_ERROR,
               "No input streams but output needs an input stream\n");
        exit_program(1);
    }

    if (!(oc->oformat->flags & AVFMT_NOFILE)) {
        /* test if it already exists to avoid losing precious files */
        assert_file_overwrite(filename);

        /* open the file */
        if ((err = avio_open2(&oc->pb, filename, AVIO_FLAG_WRITE,
                              &oc->interrupt_callback,
                              &of->opts)) < 0) {
            print_error(filename, err);
            exit_program(1);
        }
    } else if (strcmp(oc->oformat->name, "image2")==0 && !av_filename_number_test(filename))
        assert_file_overwrite(filename);

    if (o->mux_preload) {
        av_dict_set_int(&of->opts, "preload", o->mux_preload*AV_TIME_BASE, 0);
    }
    oc->max_delay = (int)(o->mux_max_delay * AV_TIME_BASE);

    /* copy metadata */
    for (i = 0; i < o->nb_metadata_map; i++) {
        char *p;
        int in_file_index = strtol(o->metadata_map[i].u.str, &p, 0);

        if (in_file_index >= nb_input_files) {
            av_log(NULL, AV_LOG_FATAL, "Invalid input file index %d while processing metadata maps\n", in_file_index);
            exit_program(1);
        }
        fftools_copy_metadata(o->metadata_map[i].specifier, *p ? p + 1 : p, oc,
                      in_file_index >= 0 ?
                      input_files[in_file_index]->ctx : NULL, o);
    }

    /* copy chapters */
    if (o->chapters_input_file >= nb_input_files) {
        if (o->chapters_input_file == INT_MAX) {
            /* copy chapters from the first input file that has them*/
            o->chapters_input_file = -1;
            for (i = 0; i < nb_input_files; i++)
                if (input_files[i]->ctx->nb_chapters) {
                    o->chapters_input_file = i;
                    break;
                }
        } else {
            av_log(NULL, AV_LOG_FATAL, "Invalid input file index %d in chapter mapping.\n",
                   o->chapters_input_file);
            exit_program(1);
        }
    }
    if (o->chapters_input_file >= 0)
        copy_chapters(input_files[o->chapters_input_file], of, oc,
                      !o->metadata_chapters_manual);

    /* copy global metadata by default */
    if (!o->metadata_global_manual && nb_input_files){
        av_dict_copy(&oc->metadata, input_files[0]->ctx->metadata,
                     AV_DICT_DONT_OVERWRITE);
        if(o->recording_time != INT64_MAX)
            av_dict_set(&oc->metadata, "duration", NULL, 0);
        av_dict_set(&oc->metadata, "creation_time", NULL, 0);
        av_dict_set(&oc->metadata, "company_name", NULL, 0);
        av_dict_set(&oc->metadata, "product_name", NULL, 0);
        av_dict_set(&oc->metadata, "product_version", NULL, 0);
    }
    if (!o->metadata_streams_manual)
        for (i = of->ost_index; i < nb_output_streams; i++) {
            InputStream *ist;
            if (output_streams[i]->source_index < 0)         /* this is true e.g. for attached files */
                continue;
            ist = input_streams[output_streams[i]->source_index];
            av_dict_copy(&output_streams[i]->st->metadata, ist->st->metadata, AV_DICT_DONT_OVERWRITE);
            if (!output_streams[i]->stream_copy) {
                av_dict_set(&output_streams[i]->st->metadata, "encoder", NULL, 0);
            }
        }

    /* process manually set programs */
    for (i = 0; i < o->nb_program; i++) {
        const char *p = o->program[i].u.str;
        int progid = i+1;
        AVProgram *program;

        while(*p) {
            const char *p2 = av_get_token(&p, ":");
            const char *to_dealloc = p2;
            char *key;
            if (!p2)
                break;

            if(*p) p++;

            key = av_get_token(&p2, "=");
            if (!key || !*p2) {
                av_freep(&to_dealloc);
                av_freep(&key);
                break;
            }
            p2++;

            if (!strcmp(key, "program_num"))
                progid = strtol(p2, NULL, 0);
            av_freep(&to_dealloc);
            av_freep(&key);
        }

        program = av_new_program(oc, progid);

        p = o->program[i].u.str;
        while(*p) {
            const char *p2 = av_get_token(&p, ":");
            const char *to_dealloc = p2;
            char *key;
            if (!p2)
                break;
            if(*p) p++;

            key = av_get_token(&p2, "=");
            if (!key) {
                av_log(NULL, AV_LOG_FATAL,
                       "No '=' character in program string %s.\n",
                       p2);
                exit_program(1);
            }
            if (!*p2)
                exit_program(1);
            p2++;

            if (!strcmp(key, "title")) {
                av_dict_set(&program->metadata, "title", p2, 0);
            } else if (!strcmp(key, "program_num")) {
            } else if (!strcmp(key, "st")) {
                int st_num = strtol(p2, NULL, 0);
                av_program_add_stream_index(oc, progid, st_num);
            } else {
                av_log(NULL, AV_LOG_FATAL, "Unknown program key %s.\n", key);
                exit_program(1);
            }
            av_freep(&to_dealloc);
            av_freep(&key);
        }
    }

    /* process manually set metadata */
    for (i = 0; i < o->nb_metadata; i++) {
        AVDictionary **m;
        char type, *val;
        const char *stream_spec;
        int index = 0, j, ret = 0;

        val = strchr(o->metadata[i].u.str, '=');
        if (!val) {
            av_log(NULL, AV_LOG_FATAL, "No '=' character in metadata string %s.\n",
                   o->metadata[i].u.str);
            exit_program(1);
        }
        *val++ = 0;

        parse_meta_type(o->metadata[i].specifier, &type, &index, &stream_spec);
        if (type == 's') {
            for (j = 0; j < oc->nb_streams; j++) {
                ost = output_streams[nb_output_streams - oc->nb_streams + j];
                if ((ret = check_stream_specifier(oc, oc->streams[j], stream_spec)) > 0) {
                    if (!strcmp(o->metadata[i].u.str, "rotate")) {
                        char *tail;
                        double theta = av_strtod(val, &tail);
                        if (!*tail) {
                            ost->rotate_overridden = 1;
                            ost->rotate_override_value = theta;
                        }
                    } else {
                        av_dict_set(&oc->streams[j]->metadata, o->metadata[i].u.str, *val ? val : NULL, 0);
                    }
                } else if (ret < 0)
                    exit_program(1);
            }
        }
        else {
            switch (type) {
            case 'g':
                m = &oc->metadata;
                break;
            case 'c':
                if (index < 0 || index >= oc->nb_chapters) {
                    av_log(NULL, AV_LOG_FATAL, "Invalid chapter index %d in metadata specifier.\n", index);
                    exit_program(1);
                }
                m = &oc->chapters[index]->metadata;
                break;
            case 'p':
                if (index < 0 || index >= oc->nb_programs) {
                    av_log(NULL, AV_LOG_FATAL, "Invalid program index %d in metadata specifier.\n", index);
                    exit_program(1);
                }
                m = &oc->programs[index]->metadata;
                break;
            default:
                av_log(NULL, AV_LOG_FATAL, "Invalid metadata specifier %s.\n", o->metadata[i].specifier);
                exit_program(1);
            }
            av_dict_set(m, o->metadata[i].u.str, *val ? val : NULL, 0);
        }
    }

    err = set_dispositions(of, oc);
    if (err < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error setting output stream dispositions\n");
        exit_program(1);
    }

    return 0;
}

int opt_target(void *optctx, const char *opt, const char *arg)
{
    const OptionDef *options = ffmpeg_options;
    OptionsContext *o = optctx;
    enum { PAL, NTSC, FILM, UNKNOWN } norm = UNKNOWN;
    static const char *const frame_rates[] = { "25", "30000/1001", "24000/1001" };

    if (!strncmp(arg, "pal-", 4)) {
        norm = PAL;
        arg += 4;
    } else if (!strncmp(arg, "ntsc-", 5)) {
        norm = NTSC;
        arg += 5;
    } else if (!strncmp(arg, "film-", 5)) {
        norm = FILM;
        arg += 5;
    } else {
        /* Try to determine PAL/NTSC by peeking in the input files */
        if (nb_input_files) {
            int i, j;
            for (j = 0; j < nb_input_files; j++) {
                for (i = 0; i < input_files[j]->nb_streams; i++) {
                    AVStream *st = input_files[j]->ctx->streams[i];
                    int64_t fr;
                    if (st->codecpar->codec_type != AVMEDIA_TYPE_VIDEO)
                        continue;
                    fr = st->time_base.den * 1000LL / st->time_base.num;
                    if (fr == 25000) {
                        norm = PAL;
                        break;
                    } else if ((fr == 29970) || (fr == 23976)) {
                        norm = NTSC;
                        break;
                    }
                }
                if (norm != UNKNOWN)
                    break;
            }
        }
        if (norm != UNKNOWN)
            av_log(NULL, AV_LOG_INFO, "Assuming %s for target.\n", norm == PAL ? "PAL" : "NTSC");
    }

    if (norm == UNKNOWN) {
        av_log(NULL, AV_LOG_FATAL, "Could not determine norm (PAL/NTSC/NTSC-Film) for target.\n");
        av_log(NULL, AV_LOG_FATAL, "Please prefix target with \"pal-\", \"ntsc-\" or \"film-\",\n");
        av_log(NULL, AV_LOG_FATAL, "or set a framerate with \"-r xxx\".\n");
        exit_program(1);
    }

    if (!strcmp(arg, "vcd")) {
        opt_video_codec(o, "c:v", "mpeg1video");
        opt_audio_codec(o, "c:a", "mp2");
        parse_option(o, "f", "vcd", options);

        parse_option(o, "s", norm == PAL ? "352x288" : "352x240", options);
        parse_option(o, "r", frame_rates[norm], options);
        opt_default(NULL, "g", norm == PAL ? "15" : "18");

        opt_default(NULL, "b:v", "1150000");
        opt_default(NULL, "maxrate:v", "1150000");
        opt_default(NULL, "minrate:v", "1150000");
        opt_default(NULL, "bufsize:v", "327680"); // 40*1024*8;

        opt_default(NULL, "b:a", "224000");
        parse_option(o, "ar", "44100", options);
        parse_option(o, "ac", "2", options);

        opt_default(NULL, "packetsize", "2324");
        opt_default(NULL, "muxrate", "1411200"); // 2352 * 75 * 8;

        /* We have to offset the PTS, so that it is consistent with the SCR.
           SCR starts at 36000, but the first two packs contain only padding
           and the first pack from the other stream, respectively, may also have
           been written before.
           So the real data starts at SCR 36000+3*1200. */
        o->mux_preload = (36000 + 3 * 1200) / 90000.0; // 0.44
    } else if (!strcmp(arg, "svcd")) {

        opt_video_codec(o, "c:v", "mpeg2video");
        opt_audio_codec(o, "c:a", "mp2");
        parse_option(o, "f", "svcd", options);

        parse_option(o, "s", norm == PAL ? "480x576" : "480x480", options);
        parse_option(o, "r", frame_rates[norm], options);
        parse_option(o, "pix_fmt", "yuv420p", options);
        opt_default(NULL, "g", norm == PAL ? "15" : "18");

        opt_default(NULL, "b:v", "2040000");
        opt_default(NULL, "maxrate:v", "2516000");
        opt_default(NULL, "minrate:v", "0"); // 1145000;
        opt_default(NULL, "bufsize:v", "1835008"); // 224*1024*8;
        opt_default(NULL, "scan_offset", "1");

        opt_default(NULL, "b:a", "224000");
        parse_option(o, "ar", "44100", options);

        opt_default(NULL, "packetsize", "2324");

    } else if (!strcmp(arg, "dvd")) {

        opt_video_codec(o, "c:v", "mpeg2video");
        opt_audio_codec(o, "c:a", "ac3");
        parse_option(o, "f", "dvd", options);

        parse_option(o, "s", norm == PAL ? "720x576" : "720x480", options);
        parse_option(o, "r", frame_rates[norm], options);
        parse_option(o, "pix_fmt", "yuv420p", options);
        opt_default(NULL, "g", norm == PAL ? "15" : "18");

        opt_default(NULL, "b:v", "6000000");
        opt_default(NULL, "maxrate:v", "9000000");
        opt_default(NULL, "minrate:v", "0"); // 1500000;
        opt_default(NULL, "bufsize:v", "1835008"); // 224*1024*8;

        opt_default(NULL, "packetsize", "2048");  // from www.mpucoder.com: DVD sectors contain 2048 bytes of data, this is also the size of one pack.
        opt_default(NULL, "muxrate", "10080000"); // from mplex project: data_rate = 1260000. mux_rate = data_rate * 8

        opt_default(NULL, "b:a", "448000");
        parse_option(o, "ar", "48000", options);

    } else if (!strncmp(arg, "dv", 2)) {

        parse_option(o, "f", "dv", options);

        parse_option(o, "s", norm == PAL ? "720x576" : "720x480", options);
        parse_option(o, "pix_fmt", !strncmp(arg, "dv50", 4) ? "yuv422p" :
                          norm == PAL ? "yuv420p" : "yuv411p", options);
        parse_option(o, "r", frame_rates[norm], options);

        parse_option(o, "ar", "48000", options);
        parse_option(o, "ac", "2", options);

    } else {
        av_log(NULL, AV_LOG_ERROR, "Unknown target: %s\n", arg);
        return AVERROR(EINVAL);
    }

    av_dict_copy(&o->g->codec_opts,  codec_opts, AV_DICT_DONT_OVERWRITE);
    av_dict_copy(&o->g->format_opts, format_opts, AV_DICT_DONT_OVERWRITE);

    return 0;
}

int opt_vstats_file(void *optctx, const char *opt, const char *arg)
{
    av_free (vstats_filename);
    vstats_filename = av_strdup (arg);
    return 0;
}

int opt_vstats(void *optctx, const char *opt, const char *arg)
{
    char filename[40];
    time_t today2 = time(NULL);
    struct tm *today = localtime(&today2);

    if (!today) { // maybe tomorrow
        av_log(NULL, AV_LOG_FATAL, "Unable to get current time: %s\n", strerror(errno));
        exit_program(1);
    }

    snprintf(filename, sizeof(filename), "vstats_%02d%02d%02d.log", today->tm_hour, today->tm_min,
             today->tm_sec);
    return opt_vstats_file(NULL, opt, filename);
}

int opt_video_frames(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "frames:v", arg, ffmpeg_options);
}

int opt_audio_frames(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "frames:a", arg, ffmpeg_options);
}

int opt_data_frames(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "frames:d", arg, ffmpeg_options);
}

int opt_default_new(OptionsContext *o, const char *opt, const char *arg)
{
    int ret;
    AVDictionary *cbak = codec_opts;
    AVDictionary *fbak = format_opts;
    codec_opts = NULL;
    format_opts = NULL;

    ret = opt_default(NULL, opt, arg);

    av_dict_copy(&o->g->codec_opts , codec_opts, 0);
    av_dict_copy(&o->g->format_opts, format_opts, 0);
    av_dict_free(&codec_opts);
    av_dict_free(&format_opts);
    codec_opts = cbak;
    format_opts = fbak;

    return ret;
}

int opt_preset(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    FILE *f=NULL;
    char filename[1000], line[1000], tmp_line[1000];
    const char *codec_name = NULL;

    tmp_line[0] = *opt;
    tmp_line[1] = 0;
    MATCH_PER_TYPE_OPT(codec_names, str, codec_name, NULL, tmp_line);

    if (!(f = get_preset_file(filename, sizeof(filename), arg, *opt == 'f', codec_name))) {
        if(!strncmp(arg, "libx264-lossless", strlen("libx264-lossless"))){
            av_log(NULL, AV_LOG_FATAL, "Please use -preset <speed> -qp 0\n");
        }else
            av_log(NULL, AV_LOG_FATAL, "File for preset '%s' not found\n", arg);
        exit_program(1);
    }

    while (fgets(line, sizeof(line), f)) {
        char *key = tmp_line, *value, *endptr;

        if (strcspn(line, "#\n\r") == 0)
            continue;
        av_strlcpy(tmp_line, line, sizeof(tmp_line));
        if (!av_strtok(key,   "=",    &value) ||
            !av_strtok(value, "\r\n", &endptr)) {
            av_log(NULL, AV_LOG_FATAL, "%s: Invalid syntax: '%s'\n", filename, line);
            exit_program(1);
        }
        av_log(NULL, AV_LOG_DEBUG, "ffpreset[%s]: set '%s' = '%s'\n", filename, key, value);

        if      (!strcmp(key, "acodec")) opt_audio_codec   (o, key, value);
        else if (!strcmp(key, "vcodec")) opt_video_codec   (o, key, value);
        else if (!strcmp(key, "scodec")) opt_subtitle_codec(o, key, value);
        else if (!strcmp(key, "dcodec")) opt_data_codec    (o, key, value);
        else if (opt_default_new(o, key, value) < 0) {
            av_log(NULL, AV_LOG_FATAL, "%s: Invalid option or argument: '%s', parsed as '%s' = '%s'\n",
                   filename, line, key, value);
            exit_program(1);
        }
    }

    fclose(f);

    return 0;
}

int opt_old2new(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    int ret;
    char *s = av_asprintf("%s:%c", opt + 1, *opt);
    if (!s)
        return AVERROR(ENOMEM);
    ret = parse_option(o, s, arg, ffmpeg_options);
    av_free(s);
    return ret;
}

int opt_bitrate(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;

    if(!strcmp(opt, "ab")){
        av_dict_set(&o->g->codec_opts, "b:a", arg, 0);
        return 0;
    } else if(!strcmp(opt, "b")){
        av_log(NULL, AV_LOG_WARNING, "Please use -b:a or -b:v, -b is ambiguous\n");
        av_dict_set(&o->g->codec_opts, "b:v", arg, 0);
        return 0;
    }
    av_dict_set(&o->g->codec_opts, opt, arg, 0);
    return 0;
}

int opt_qscale(void *optctx, const char *opt, const char *arg)
{
    OptionDef *options = ffmpeg_options;
    OptionsContext *o = optctx;
    char *s;
    int ret;
    if(!strcmp(opt, "qscale")){
        av_log(NULL, AV_LOG_WARNING, "Please use -q:a or -q:v, -qscale is ambiguous\n");
        return parse_option(o, "q:v", arg, options);
    }
    s = av_asprintf("q%s", opt + 6);
    if (!s)
        return AVERROR(ENOMEM);
    ret = parse_option(o, s, arg, options);
    av_free(s);
    return ret;
}

int opt_profile(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    if(!strcmp(opt, "profile")){
        av_log(NULL, AV_LOG_WARNING, "Please use -profile:a or -profile:v, -profile is ambiguous\n");
        av_dict_set(&o->g->codec_opts, "profile:v", arg, 0);
        return 0;
    }
    av_dict_set(&o->g->codec_opts, opt, arg, 0);
    return 0;
}

int opt_video_filters(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "filter:v", arg, ffmpeg_options);
}

int opt_audio_filters(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "filter:a", arg, ffmpeg_options);
}

int opt_vsync(void *optctx, const char *opt, const char *arg)
{
    av_log(NULL, AV_LOG_WARNING, "-vsync is deprecated. Use -fps_mode\n");
    parse_and_set_vsync(arg, &video_sync_method, -1, -1, 1);
    return 0;
}

int opt_timecode(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    int ret;
    char *tcr = av_asprintf("timecode=%s", arg);
    if (!tcr)
        return AVERROR(ENOMEM);
    ret = parse_option(o, "metadata:g", tcr, ffmpeg_options);
    if (ret >= 0)
        ret = av_dict_set(&o->g->codec_opts, "gop_timecode", arg, 0);
    av_free(tcr);
    return ret;
}

int opt_audio_qscale(void *optctx, const char *opt, const char *arg)
{
    OptionsContext *o = optctx;
    return parse_option(o, "q:a", arg, ffmpeg_options);
}

int opt_filter_complex(void *optctx, const char *opt, const char *arg)
{
    FilterGraph *fg = ALLOC_ARRAY_ELEM(filtergraphs, nb_filtergraphs);

    fg->index      = nb_filtergraphs - 1;
    fg->graph_desc = av_strdup(arg);
    if (!fg->graph_desc)
        return AVERROR(ENOMEM);

    input_stream_potentially_available = 1;

    return 0;
}

int opt_filter_complex_script(void *optctx, const char *opt, const char *arg)
{
    FilterGraph *fg;
    char *graph_desc = fftools_read_file(arg);
    if (!graph_desc)
        return AVERROR(EINVAL);

    fg = ALLOC_ARRAY_ELEM(filtergraphs, nb_filtergraphs);
    fg->index      = nb_filtergraphs - 1;
    fg->graph_desc = graph_desc;

    input_stream_potentially_available = 1;

    return 0;
}

void show_help_default_ffmpeg(const char *opt, const char *arg)
{
    OptionDef *options = ffmpeg_options;
    /* per-file options have at least one of those set */
    const int per_file = OPT_SPEC | OPT_OFFSET | OPT_PERFILE;
    int show_advanced = 0, show_avoptions = 0;

    if (opt && *opt) {
        if (!strcmp(opt, "long"))
            show_advanced = 1;
        else if (!strcmp(opt, "full"))
            show_advanced = show_avoptions = 1;
        else
            av_log(NULL, AV_LOG_ERROR, "Unknown help option '%s'.\n", opt);
    }

    show_usage();

    av_log(NULL, AV_LOG_STDERR, "Getting help:\n"
           "    -h      -- print basic options\n"
           "    -h long -- print more options\n"
           "    -h full -- print all options (including all format and codec specific options, very long)\n"
           "    -h type=name -- print all options for the named decoder/encoder/demuxer/muxer/filter/bsf/protocol\n"
           "    See man %s for detailed description of the options.\n"
           "\n", program_name);

    show_help_options(options, "Print help / information / capabilities:",
                      OPT_EXIT, 0, 0);

    show_help_options(options, "Global options (affect whole program "
                      "instead of just one file):",
                      0, per_file | OPT_EXIT | OPT_EXPERT, 0);
    if (show_advanced)
        show_help_options(options, "Advanced global options:", OPT_EXPERT,
                          per_file | OPT_EXIT, 0);

    show_help_options(options, "Per-file main options:", 0,
                      OPT_EXPERT | OPT_AUDIO | OPT_VIDEO | OPT_SUBTITLE |
                      OPT_EXIT, per_file);
    if (show_advanced)
        show_help_options(options, "Advanced per-file options:",
                          OPT_EXPERT, OPT_AUDIO | OPT_VIDEO | OPT_SUBTITLE, per_file);

    show_help_options(options, "Video options:",
                      OPT_VIDEO, OPT_EXPERT | OPT_AUDIO, 0);
    if (show_advanced)
        show_help_options(options, "Advanced Video options:",
                          OPT_EXPERT | OPT_VIDEO, OPT_AUDIO, 0);

    show_help_options(options, "Audio options:",
                      OPT_AUDIO, OPT_EXPERT | OPT_VIDEO, 0);
    if (show_advanced)
        show_help_options(options, "Advanced Audio options:",
                          OPT_EXPERT | OPT_AUDIO, OPT_VIDEO, 0);
    show_help_options(options, "Subtitle options:",
                      OPT_SUBTITLE, 0, 0);
    av_log(NULL, AV_LOG_STDERR, "\n");

    if (show_avoptions) {
        int flags = AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_ENCODING_PARAM;
        show_help_children(avcodec_get_class(), flags);
        show_help_children(avformat_get_class(), flags);
#if CONFIG_SWSCALE
        show_help_children(sws_get_class(), flags);
#endif
#if CONFIG_SWRESAMPLE
        show_help_children(swr_get_class(), AV_OPT_FLAG_AUDIO_PARAM);
#endif
        show_help_children(avfilter_get_class(), AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM);
        show_help_children(av_bsf_get_class(), AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_BSF_PARAM);
    }
}

void show_usage(void)
{
    av_log(NULL, AV_LOG_INFO, "Hyper fast Audio and Video encoder\n");
    av_log(NULL, AV_LOG_INFO, "usage: %s [options] [[infile options] -i infile]... {[outfile options] outfile}...\n", program_name);
    av_log(NULL, AV_LOG_INFO, "\n");
}

enum OptGroup {
    GROUP_OUTFILE,
    GROUP_INFILE,
};

static const OptionGroupDef groups[] = {
    [GROUP_OUTFILE] = { "output url",  NULL, OPT_OUTPUT },
    [GROUP_INFILE]  = { "input url",   "i",  OPT_INPUT },
};

int open_files(OptionGroupList *l, const char *inout,
                      int (*open_file)(OptionsContext*, const char*))
{
    int i, ret;

    for (i = 0; i < l->nb_groups; i++) {
        OptionGroup *g = &l->groups[i];
        OptionsContext o;

        init_options(&o);
        o.g = g;

        ret = parse_optgroup(&o, g);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error parsing options for %s file "
                   "%s.\n", inout, g->arg);
            uninit_options(&o);
            return ret;
        }

        av_log(NULL, AV_LOG_DEBUG, "Opening an %s file: %s.\n", inout, g->arg);
        ret = open_file(&o, g->arg);
        uninit_options(&o);
        if (ret < 0) {
            av_log(NULL, AV_LOG_ERROR, "Error opening %s file %s.\n",
                   inout, g->arg);
            return ret;
        }
        av_log(NULL, AV_LOG_DEBUG, "Successfully opened the file.\n");
    }

    return 0;
}

int ffmpeg_parse_options(int argc, char **argv)
{
    OptionParseContext octx;
    uint8_t error[128];
    int ret;

    memset(&octx, 0, sizeof(octx));

    /* split the commandline into an internal representation */
    ret = split_commandline(&octx, argc, argv, ffmpeg_options, groups,
                            FF_ARRAY_ELEMS(groups));
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error splitting the argument list: ");
        goto fail;
    }

    /* apply global options */
    ret = parse_optgroup(NULL, &octx.global_opts);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error parsing global options: ");
        goto fail;
    }

    /* configure terminal and setup signal handlers */
    term_init();

    /* open input files */
    ret = open_files(&octx.groups[GROUP_INFILE], "input", open_input_file);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error opening input files: ");
        goto fail;
    }

    apply_sync_offsets();

    /* create the complex filtergraphs */
    ret = init_complex_filters();
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error initializing complex filters.\n");
        goto fail;
    }

    /* open output files */
    ret = open_files(&octx.groups[GROUP_OUTFILE], "output", open_output_file);
    if (ret < 0) {
        av_log(NULL, AV_LOG_FATAL, "Error opening output files: ");
        goto fail;
    }

    check_filter_outputs();

fail:
    uninit_parse_context(&octx);
    if (ret < 0) {
        av_strerror(ret, error, sizeof(error));
        av_log(NULL, AV_LOG_FATAL, "%s\n", error);
    }
    return ret;
}

int opt_progress(void *optctx, const char *opt, const char *arg)
{
    AVIOContext *avio = NULL;
    int ret;

    if (!strcmp(arg, "-"))
        arg = "pipe:";
    ret = avio_open2(&avio, arg, AVIO_FLAG_WRITE, &int_cb, NULL);
    if (ret < 0) {
        av_log(NULL, AV_LOG_ERROR, "Failed to open progress URL \"%s\": %s\n",
               arg, av_err2str(ret));
        return ret;
    }
    progress_avio = avio;
    return 0;
}

int opt_timelimit(void *optctx, const char *opt, const char *arg)
{
#if HAVE_SETRLIMIT
    int lim = parse_number_or_die(opt, arg, OPT_INT64, 0, INT_MAX);
    struct rlimit rl = { lim, lim + 1 };
    if (setrlimit(RLIMIT_CPU, &rl))
        perror("setrlimit");
#else
    av_log(NULL, AV_LOG_WARNING, "-%s not implemented on this OS\n", opt);
#endif
    return 0;
}
